| Records |
| Author |
Steinhoff, H.J.; Schrader, J.; Schlitter, J. |
| Title |
Temperature-jump studies and polarized absorption spectroscopy of methemoglobin-thiocyanate single crystals |
Type |
Journal Article |
| Year |
1992 |
Publication |
Biochimica et Biophysica Acta |
Abbreviated Journal |
Biochim Biophys Acta |
| Volume |
1121 |
Issue |
3 |
Pages |
269-278 |
| Keywords |
Animals; Crystallization; Horses; Kinetics; Methemoglobin/*chemistry; Solutions; Spectrum Analysis; Temperature; Thiocyanates/*chemistry |
| Abstract |
Association equilibria and association kinetics of the thiocyanate binding reaction to methemoglobin in single crystals and solution are studied using temperature-jump technique and polarized absorption spectroscopy. Different kinetic constants are found for the reaction in solution and crystal phase for the alpha- and beta-subunits of the methemoglobin tetramer. The reduction of the reactivity of the alpha- and beta-subunits in crystalline phase is 6-fold and 2.4-fold, respectively, compared to the values found in solution. The intramolecular binding reaction of the N epsilon of the distal histidine E7 which is observed in methemoglobin in solution cannot be detected in single crystals. Our results suggest that crystallization of hemoglobin has little influence on small-scale structural fluctuations which are necessary for ligands to get to the binding sites and large-scale structural motions are suppressed. |
| Address |
Institut fur Biophysik, Ruhr-Universitat Bochum, Germany |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title  |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0006-3002 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:1627604 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3800 |
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| Author |
Steinhoff, H.J. |
| Title |
A continuous wave laser T-jump apparatus and its application to chemical reactions in hemoglobin single crystals |
Type |
Journal Article |
| Year |
1988 |
Publication |
Journal of Biochemical and Biophysical Methods |
Abbreviated Journal |
J Biochem Biophys Methods |
| Volume |
15 |
Issue |
6 |
Pages |
319-330 |
| Keywords |
Animals; Chemistry; Crystallization; *Heat; *Hemoglobins; Horses/blood; *Lasers; Methemoglobin; Solutions; Thermodynamics; Thiocyanates |
| Abstract |
A laser temperature jump apparatus is constructed where the T-jump is achieved by means of the direct absorption of continuous laser radiation of low intensity by a solid sample. The final temperature in the irradiated volume element is reached when the absorbed radiation power equals the dissipation of heat by heat conduction. The time range from the beginning of irradiation to the stationary state depends on the geometry of the irradiated volume element and is less than 10 ms. The heating laser beam is simultaneously used to detect the relaxation to the new chemical equilibrium in the sample. Relaxation processes with relaxation rates between 10(2) s-1 and less than 10(-3) s-1 on samples with volumes less than 10(-3) mm3 may be investigated using this T-jump method. One application of this method is the determination of reaction rates of ligand reactions in hemoglobin single crystals. Rate constants obtained for the reaction of thiocyanate with crystallized horse methemoglobin are presented. |
| Address |
Institut fur Biophysik, Ruhr-Universitat Bochum, F.R.G |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0165-022X |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:3379245 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3804 |
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| |
| Author |
Pierce, M.M.; Nall, B.T. |
| Title |
Coupled kinetic traps in cytochrome c folding: His-heme misligation and proline isomerization |
Type |
Journal Article |
| Year |
2000 |
Publication |
Journal of Molecular Biology |
Abbreviated Journal |
J Mol Biol |
| Volume |
298 |
Issue |
5 |
Pages |
955-969 |
| Keywords |
Amino Acid Sequence; Amino Acid Substitution/genetics; Binding Sites; Cytochrome c Group/*chemistry/genetics/*metabolism; *Cytochromes c; Enzyme Stability/drug effects; Fluorescence; Guanidine/pharmacology; Heme/*metabolism; Histidine/genetics/*metabolism; Hydrogen-Ion Concentration; Isomerism; Kinetics; Models, Molecular; Molecular Sequence Data; Mutation/genetics; Proline/*chemistry/metabolism; Protein Conformation/drug effects; Protein Denaturation/drug effects; *Protein Folding; Protein Renaturation; Saccharomyces cerevisiae/enzymology/genetics; Sequence Alignment; Thermodynamics |
| Abstract |
The effect of His-heme misligation on folding has been investigated for a triple mutant of yeast iso-2 cytochrome c (N26H,H33N,H39K iso-2). The variant contains a single misligating His residue at position 26, a location at which His residues are found in several cytochrome c homologues, including horse, tuna, and yeast iso-1. The amplitude for fast phase folding exhibits a strong initial pH dependence. For GdnHCl unfolded protein at an initial pH<5, the observed refolding at final pH 6 is dominated by a fast phase (tau(2f)=20 ms, alpha(2f)=90 %) that represents folding in the absence of misligation. For unfolded protein at initial pH 6, folding at final pH 6 occurs in a fast phase of reduced amplitude (alpha(2f) approximately 20 %) but the same rate (tau(2f)=20 ms), and in two slower phases (tau(m)=6-8 seconds, alpha(m) approximately 45 %; and tau(1b)=16-20 seconds, alpha(1b) approximately 35 %). Double jump experiments show that the initial pH dependence of the folding amplitudes results from a slow pH-dependent equilibrium between fast and slow folding species present in the unfolded protein. The slow equilibrium arises from coupling of the His protonation equilibrium to His-heme misligation and proline isomerization. Specifically, Pro25 is predominantly in trans in the unligated low-pH unfolded protein, but is constrained in a non-native cis isomerization state by His26-heme misligation near neutral pH. Refolding from the misligated unfolded form proceeds slowly due to the large energetic barrier required for proline isomerization and displacement of the misligated His26-heme ligand. |
| Address |
Center for Biomolecular Structure, Department of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0022-2836 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:10801361 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
3853 |
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| Author |
Franceschini, C.; Siutz, C.; Palme, R.; Millesi, E. |
| Title |
Seasonal changes in cortisol and progesterone secretion in Common hamsters |
Type |
Journal Article |
| Year |
2007 |
Publication |
General and Comparative Endocrinology |
Abbreviated Journal |
Gen Comp Endocrinol |
| Volume |
152 |
Issue |
1 |
Pages |
14-21 |
| Keywords |
Animals; Cortisone/*secretion; Cricetinae/*metabolism; Feces/chemistry; Female; Lactation/physiology; Male; Pregnancy; Progesterone/*secretion; Reproduction/physiology; *Seasons; Sexual Behavior, Animal/physiology |
| Abstract |
In this study, we investigated endocrine factors and behaviour in free-living Common hamsters (Cricetus cricetus) during reproductive and non-reproductive periods of the annual cycle. We applied a non-invasive method to gain information on seasonal changes in adrenocortical activity in male and female hamsters by analysing faecal glucocorticoid metabolite concentrations (FCM). In addition, plasma progesterone concentrations were monitored in females throughout the non-hibernation season. The animals were live-trapped from spring emergence until the onset of hibernation in autumn. Reproductive status was determined at capture and blood and faecal samples were collected. During behavioural observations, agonistic and sexual interactions were recorded. FCM concentrations were significantly higher in males than in females during the reproductive period. In males, a pronounced increase in FCM during the reproductive period coincided with high frequencies of intrasexual aggression. In females, FCM levels remained relatively constant. Aggressive behaviour in females increased during the reproductive period, but was much less frequent than in males. Females, which successfully raised a second litter after a postpartum oestrus and concurrent lactation and gestation had lower FCM levels than individuals, which lost their second litter after parturition. As expected, plasma progesterone concentrations were low before and after the reproductive period. During gestation, levels peaked and remained elevated during lactation. The results of this field study provide insight in critical periods associated with reproduction in male and female Common hamsters. |
| Address |
Department of Behavioural Biology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. claudia.franceschini@univie.ac.ct |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0016-6480 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:17408667 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4076 |
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| Author |
Heistermann, M.; Palme, R.; Ganswindt, A. |
| Title |
Comparison of different enzyme-immunoassays for assessment of adrenocortical activity in primates based on fecal analysis |
Type |
Journal Article |
| Year |
2006 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
| Volume |
68 |
Issue |
3 |
Pages |
257-273 |
| Keywords |
11-Hydroxycorticosteroids/*analysis; Adrenocorticotropic Hormone/pharmacology; Anesthesia; Animals; Corticosterone/analysis; Feces/*chemistry; Glucocorticoids/*analysis; Haplorhini/*metabolism; Hydrocortisone/analysis; Hypothalamo-Hypophyseal System/drug effects/physiology; Immunoenzyme Techniques/*methods; Pituitary-Adrenal System/drug effects/physiology; Species Specificity |
| Abstract |
Most studies published to date that used fecal glucocorticoid measurements to assess adrenocortical activity in primate (and many nonprimate) species applied a specific cortisol or corticosterone assay. However, since these native glucocorticoids are virtually absent in the feces of most vertebrates, including primates, the validity of this approach has recently been questioned. Therefore, the overall aim of the present study was to assess the validity of four enzyme-immunoassays (EIAs) using antibodies raised against cortisol, corticosterone, and reduced cortisol metabolites (two group-specific antibodies) for assessing adrenocortical activity using fecal glucocorticoid metabolite (GCM) measurements in selected primate species (marmoset, long-tailed macaque, Barbary macaque, chimpanzee, and gorilla). Using physiological stimulation of the hypothalamo-pituitary-adrenocortical (HPA) axis by administering exogenous ACTH or anesthesia, we demonstrated that at least two assays detected the predicted increase in fecal GCM levels in response to treatment in each species. However, the magnitude of response varied between assays and species, and no one assay was applicable to all species. While the corticosterone assay generally was of only limited suitability for assessing glucocorticoid output, the specific cortisol assay was valuable for those species that (according to high-performance liquid chromatography (HPLC) analysis data) excreted clearly detectable amounts of authentic cortisol into the feces. In contrast, in species in which cortisol was virtually absent in the feces, group-specific assays provided a much stronger signal, and these assays also performed well in the other primate species tested (except the marmoset). Collectively, the data suggest that the reliability of a given fecal glucocorticoid assay in reflecting activity of the HPA axis in primates clearly depends on the species in question. Although to date there is no single assay system that can be used successfully across species, our data suggest that group-specific assays have a high potential for cross-species application. Nevertheless, regardless of which GC antibody is chosen, our study clearly reinforces the necessity of appropriately validating the respective assay system before it is used. |
| Address |
Department of Reproductive Biology, German Primate Center, Gottingen, Germany. mheiste@gwdg.de |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0275-2565 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:16477600 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4078 |
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| Author |
Thiel, D.; Jenni-Eiermann, S.; Palme, R. |
| Title |
Measuring corticosterone metabolites in droppings of capercaillies (Tetrao urogallus) |
Type |
Journal Article |
| Year |
2005 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann N Y Acad Sci |
| Volume |
1046 |
Issue |
|
Pages |
96-108 |
| Keywords |
Adrenocorticotropic Hormone/administration & dosage/analysis/metabolism; Animals; Circadian Rhythm; Corticosterone/administration & dosage/*analysis/*metabolism; Feces/*chemistry; Female; Freezing; Galliformes/*metabolism; Male; Reproducibility of Results; Sex Factors; Temperature; Time Factors; Tritium/diagnostic use |
| Abstract |
The capercaillie (Tetrao urogallus), the largest grouse species in the world, is decreasing in numbers in major parts of its distribution range. Disturbances by human outdoor activities are discussed as a possible reason for this population decline. An indicator for disturbances is the increase of the glucocorticoid corticosterone, a stress hormone, which helps to cope with life-threatening situations. However, repeated disturbances might result in a long-term increase of the basal corticosterone concentration, which can result in detrimental effects like reduced fitness and survival of an animal. To measure corticosterone metabolites (CMs) noninvasively in the droppings of free-living capercaillies, first an enzyme immunoassay (EIA) in captive birds had to be selected and validated. Therefore, the excretion pattern of intravenously injected radiolabeled corticosterone was determined and 3H metabolites were characterized. High-performance liquid chromatography (HPLC) separations of the samples containing peak concentrations revealed that corticosterone was extensively metabolized. The HPLC fractions were tested in several EIAs for glucocorticoid metabolites. The physiological relevance of this method was proved after pharmacological stimulation of the adrenocortical activity. Only the recently established cortisone assay, measuring CMs with a 3,11-dione structure, detected an expressed increase of concentrations following ACTH stimulation. To set up a sampling protocol suited for the field, we examined the influence of various storage conditions and time of day on concentrations of CMs. |
| Address |
Swiss Ornithological Institute, 6204 Sempach, Switzerland. dominik.thiel@vogelwarte.ch |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0077-8923 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:16055846 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4079 |
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| Author |
Baltic, M.; Jenni-Eiermann, S.; Arlettaz, R.; Palme, R. |
| Title |
A noninvasive technique to evaluate human-generated stress in the black grouse |
Type |
Journal Article |
| Year |
2005 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann N Y Acad Sci |
| Volume |
1046 |
Issue |
|
Pages |
81-95 |
| Keywords |
Adrenocorticotropic Hormone/metabolism; Animals; Bird Diseases/*metabolism; Conservation of Natural Resources; Corticosterone/*metabolism; Ecosystem; Feces/*chemistry; Female; Galliformes/*metabolism; Immunoenzyme Techniques/methods/veterinary; Male; Reproducibility of Results; Stress/metabolism/*veterinary; Tritium/diagnostic use |
| Abstract |
The continuous development of tourism and related leisure activities is exerting an increasingly intense pressure on wildlife. In this study, a novel noninvasive method for measuring stress in the black grouse, an endangered, emblematic species of European ecosystems that is currently declining in several parts of its European range, is tested and physiologically validated. A radiometabolism study and an ACTH challenge test were performed on four captive black grouse (two of each sex) in order to get basic information about the metabolism and excretion of corticosterone and to find an appropriate enzyme-immunoassay (EIA) to measure its metabolites in the feces. Peak radioactivity in the droppings was detected within 1 to 2 hours. Injected (3)H-corticosterone was excreted as polar metabolites and by itself was almost absent. A cortisone-EIA was chosen from among seven tested EIAs for different groups of glucocorticoid metabolites, because it cross-reacted with some of the formed metabolites and best reflected the increase of excreted corticosterone metabolites, after the ACTH challenge test. Concentrations of the metabolites from fecal samples collected from snow burrows of free-ranging black grouse were within the same range as in captive birds. The noninvasive method described may be appropriate for evaluating the stress faced by free-living black grouse populations in the wild, particularly in mountain ecosystems where human disturbance, especially by winter sports, is of increasing conservation concern. |
| Address |
Zoological Institute, Division of Conservation Biology, Baltzerstrasse 6, CH-3012 Bern, Switzerland |
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Place of Publication |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0077-8923 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:16055845 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4080 |
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| Author |
Mostl, E.; Rettenbacher, S.; Palme, R. |
| Title |
Measurement of corticosterone metabolites in birds' droppings: an analytical approach |
Type |
Journal Article |
| Year |
2005 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann N Y Acad Sci |
| Volume |
1046 |
Issue |
|
Pages |
17-34 |
| Keywords |
Animals; Birds/*metabolism; Corticosterone/*analysis/metabolism; Feces/*chemistry; Gas Chromatography-Mass Spectrometry; Immunoassay; Molecular Structure; Reproducibility of Results; Sensitivity and Specificity |
| Abstract |
Fecal steroid analyses are becoming increasingly popular among both field and laboratory scientists. The benefits associated with sampling procedures that do not require restraint, anesthesia, and blood collection include less risk to subject and investigator, as well as the potential to obtain endocrine profiles that are not influenced by the sampling procedure itself. In the feces, a species-specific pattern of metabolites is present, because glucocorticoids are extensively metabolized. Therefore, selection of adequate extraction procedures and immunoassays for measuring the relevant metabolites is a serious issue. In this review, emphasis is placed on the establishment and analytical validation of methods to measure glucocorticoid metabolites for a noninvasive evaluation of adrenocortical activity in droppings of birds. |
| Address |
Institute of Biochemistry, Department of Natural Sciences, University of Veterinary Medicine, Vienna, Veterinarplatz 1, A-1210 Vienna, Austria. erich.moestl@vu-wien.ac.at |
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Place of Publication |
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Editor |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0077-8923 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:16055841 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4082 |
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| Author |
Touma, C.; Palme, R.; Sachser, N. |
| Title |
Analyzing corticosterone metabolites in fecal samples of mice: a noninvasive technique to monitor stress hormones |
Type |
Journal Article |
| Year |
2004 |
Publication |
Hormones and Behavior |
Abbreviated Journal |
Horm Behav |
| Volume |
45 |
Issue |
1 |
Pages |
10-22 |
| Keywords |
Adrenal Cortex/drug effects; Adrenal Cortex Function Tests; Adrenocorticotropic Hormone/pharmacology; Analysis of Variance; Animals; Circadian Rhythm; Corticosterone/*analysis/metabolism; Dexamethasone/pharmacology; Feces/*chemistry; Female; Immunoenzyme Techniques/*methods; Male; Mice; Mice, Inbred C57BL; Models, Animal; Reproducibility of Results; Stress, Psychological/*metabolism |
| Abstract |
In small animals like mice, the monitoring of endocrine functions over time is constrained seriously by the adverse effects of blood sampling. Therefore, noninvasive techniques to monitor, for example, stress hormones in these animals are highly demanded in laboratory as well as in field research. The aim of our study was to evaluate the biological relevance of a recently developed technique to monitor stress hormone metabolites in fecal samples of laboratory mice. In total, six experiments were performed using six male and six female mice each. Two adrenocorticotropic hormone (ACTH) challenge tests, two dexamethasone (Dex) suppression tests and two control experiments [investigating effects of the injection procedure itself and the diurnal variation (DV) of glucocorticoids (GCs), respectively] were conducted. The experiments clearly demonstrated that pharmacological stimulation and suppression of adrenocortical activity was reflected accurately by means of corticosterone metabolite (CM) measurements in the feces of males and females. Furthermore, the technique proved sensitive enough to detect dosage-dependent effects of the ACTH/Dex treatment and facilitated to reveal profound effects of the injection procedure itself. Even the naturally occurring DV of GCs could be monitored reliably. Thus, our results confirm that measurement of fecal CM with the recently established 5alpha-pregnane-3beta,11beta,21-triol-20-one enzyme immunoassay is a very powerful tool to monitor adrenocortical activity in laboratory mice. Since mice represent the vast majority of all rodents used for research worldwide and the number of transgenic and knockout mice utilized as animal models is still increasing, this noninvasive technique can open new perspectives in biomedical and behavioral science. |
| Address |
Department of Behavioural Biology, University of Muenster, D-48149 Muenster, Germany. touma@uni-muenster.de |
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Place of Publication |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0018-506X |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:14733887 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4084 |
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| Author |
Ganswindt, A.; Palme, R.; Heistermann, M.; Borragan, S.; Hodges, J.K. |
| Title |
Non-invasive assessment of adrenocortical function in the male African elephant (Loxodonta africana) and its relation to musth |
Type |
Journal Article |
| Year |
2003 |
Publication |
General and Comparative Endocrinology |
Abbreviated Journal |
Gen Comp Endocrinol |
| Volume |
134 |
Issue |
2 |
Pages |
156-166 |
| Keywords |
Adrenal Cortex/*metabolism/secretion; Adrenal Cortex Function Tests/methods/*veterinary; Adrenocorticotropic Hormone/physiology; Animals; Carbon Isotopes/diagnostic use; Chromatography, High Pressure Liquid/veterinary; Elephants/*metabolism/urine; Feces/*chemistry; Glucocorticoids/analysis/urine; Hydrocortisone/*analysis/diagnostic use/urine; Immunoenzyme Techniques/methods/veterinary; Male; Reproduction/physiology; Sexual Behavior, Animal/physiology; Stress, Psychological/diagnosis/*physiopathology; Testosterone/*analysis/diagnostic use/urine |
| Abstract |
Adult male elephants periodically show the phenomenon of musth, a condition associated with increased aggressiveness, restlessness, significant weight reduction and markedly elevated androgen levels. It has been suggested that musth-related behaviours are costly and that therefore musth may represent a form of physiological stress. In order to provide data on this largely unanswered question, the first aim of this study was to evaluate different assays for non-invasive assessment of adrenocortical function in the male African elephant by (i) characterizing the metabolism and excretion of [3H]cortisol (3H-C) and [14C]testosterone (14C-T) and (ii) using this information to evaluate the specificity of four antibodies for determination of excreted cortisol metabolites, particularly with respect to possible cross-reactions with androgen metabolites, and to assess their biological validity using an ACTH challenge test. Based on the methodology established, the second objective was to provide data on fecal cortisol metabolite concentrations in bulls during the musth and non-musth condition. 3H-C (1 mCi) and 14C-T (100 microCi) were injected simultaneously into a 16 year old male and all urine and feces collected for 30 and 86 h, respectively. The majority (82%) of cortisol metabolites was excreted into the urine, whereas testosterone metabolites were mainly (57%) excreted into the feces. Almost all radioactive metabolites recovered from urine were conjugated (86% 3H-C and 97% 14C-T). In contrast, 86% and >99% of the 3H-C and 14C-T metabolites recovered from feces consisted of unconjugated forms. HPLC separations indicated the presence of various metabolites of cortisol in both urine and feces, with cortisol being abundant in hydrolysed urine, but virtually absent in feces. Although all antibodies measured substantial amounts of immunoreactivity after HPLC separation of peak radioactive samples and detected an increase in glucocorticoid output following the ACTH challenge, only two (in feces against 3alpha,11-oxo-cortisol metabolites, measured by an 11-oxo-etiocholanolone-EIA and in urine against cortisol, measured by a cortisol-EIA) did not show substantial cross-reactivity with excreted 14C-T metabolites and could provide an acceptable degree of specificity for reliable assessment of glucocorticoid output from urine and feces. Based on these findings, concentrations of immunoreactive 3alpha,11-oxo-cortisol metabolites were determined in weekly fecal samples collected from four adult bulls over periods of 11-20 months to examine whether musth is associated with increased adrenal activity. Results showed that in each male levels of these cortisol metabolites were not elevated during periods of musth, suggesting that in the African elephant musth is generally not associated with marked elevations in glucocorticoid output. Given the complex nature of musth and the variety of factors that are likely to influence its manifestation, it is clear, however, that further studies, particularly on free-ranging animals, are needed before a possible relationship between musth and adrenal function can be resolved. This study also clearly illustrates the potential problems associated with cross-reacting metabolites of gonadal steroids in EIAs measuring glucocorticoid metabolites. This has to be taken into account when selecting assays and interpreting results of glucocorticoid metabolite analysis, not only for studies in the elephant but also in other species. |
| Address |
German Primate Centre, Department of Reproductive Biology, Kellnerweg 4, 37077 Gottingen, Germany. ganswindt@www.dpz.gdwg.de |
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Editor |
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| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0016-6480 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:14511986 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4085 |
| Permanent link to this record |
