| |
Records |
Links |
|
Author |
Voss, B.; Mohr, E.; Krzywanek, H. |
|
| |
Title |
Effects of aqua-treadmill exercise on selected blood parameters and on heart-rate variability of horses |
Type |
Journal Article |
| |
Year  |
2002 |
Publication |
Journal of Veterinary Medicine. A, Physiology, Pathology, Clinical Medicine |
Abbreviated Journal |
J Vet Med A Physiol Pathol Clin Med |
|
| |
Volume |
49 |
Issue |
3 |
Pages |
137-143 |
|
| |
Keywords |
Animals; Electrocardiography/veterinary; Exercise Test/veterinary; Female; Heart Rate/*physiology; Hemoglobins/metabolism; Horses/*physiology; Lactic Acid/blood; Male; Physical Conditioning, Animal/*physiology; Water |
|
| |
Abstract |
The objectives of the present study were to investigate the effects of Aquatraining of horses (aqua-treadmill exercise; treadmill manufactured by Equitech – L.u.S. Equipment, Warendorf, Germany) on selected blood parameters [lactic acid concentration (mmol/l), haemoglobin content (g/l)] and on heart-rate variability (HRV) [heart rate (beats per min; b.p.m.), standard deviation of all NN-intervals (SDNN; ms), normalized power of the low and high frequency band (LFnorm, Hfnorm; au), % recurrence, % determinism and ratio(corr)]. Seven horses performed six exercise tests with different work loads (walking (x = 1.56 +/- 0.08 m/s) and trotting (x = 2.9 +/- 0.13 m/s): dry, water above the carpus and water above the elbow). The standardized test-protocol was: 5 min warm-up at walk while the water was pumped in, followed by the 20-min exercise period at walk or trot, followed by a 5-min walk while pumping out the water. Blood samples were taken prior to each test at rest in the stable, as well as exactly 5 min after the end of the 20-min exercise period. Electrocardiograms were recorded during rest and the 20-min exercise period. Compared to rest, neither the chosen velocities, the two water levels, nor the dry tests led to a significant increase of the lactic acid concentration in any horse. The haemoglobin content showed a significant increase as a result of exercise. Significant differences could be found between the heart rates at rest and the six exercise tests and between the mean of the levels 'walking' and the mean of the levels 'trotting'. An exercise-induced change of HRV was characterized by a decreasing SDNN, a significantly higher LFnorm (sympathetic influence) combined with a significantly lower HF(norm) power (parasympathetic activity) and a rising degree of order (significantly higher % determinism and nearly unchanged % recurrence) and stability (significantly rising ratio(corr)) of the recurrence plot. In conclusion, the used training-protocol for aqua-treadmill exercises only represents a medium-sized aerobic work load for horses, but the different levels of burden were indicated especially by changes in HRV. |
|
| |
Address |
Institute for Veterinary Physiology of the Free University Berlin, Germany |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0931-184X |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:12019954 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
4049 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Natalini, C.C.; Robinson, E.P. |
|
| |
Title |
Effects of epidural opioid analgesics on heart rate, arterial blood pressure, respiratory rate, body temperature, and behavior in horses |
Type |
Journal Article |
| |
Year |
2003 |
Publication |
Veterinary Therapeutics : Research in Applied Veterinary Medicine |
Abbreviated Journal |
Vet Ther |
|
| |
Volume |
4 |
Issue |
4 |
Pages |
364-375 |
|
| |
Keywords |
3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/administration & dosage/pharmacology; Alfentanil/administration & dosage/pharmacology; Analgesics, Opioid/administration & dosage/*pharmacology; Anesthesia, Epidural/*veterinary; Animals; Behavior, Animal/drug effects; Blood Pressure/drug effects; Body Temperature/drug effects; Butorphanol/administration & dosage/pharmacology; Cross-Over Studies; Female; Heart Rate/drug effects; Horses/*physiology; Injections, Epidural/veterinary; Male; Morphine/administration & dosage/pharmacology; Respiration/drug effects; Tramadol/administration & dosage/pharmacology |
|
| |
Abstract |
Heart rate, arterial blood pressures, respiratory rate, body temperature, and central nervous system excitement were compared before and after epidural administration of morphine (0.1 mg/kg), butorphanol (0.08 mg/kg), alfentanil (0.02 mg/kg), tramadol (1.0 mg/kg), the k-opioid agonist U50488H (0.08 mg/kg), or sterile water using an incomplete Latin square crossover design in five conscious adult horses. Treatments were administered into the first intercoccygeal epidural space. Significant (P <.05) reductions in respiratory rate were detected after epidural administration of morphine, alfentanil, U50488H, and sterile water. Additionally, significant (P <.05) head ptosis was observed within the first hour after administration of morphine, U50488H, and tramadol, but neither of these changes appeared to be of clinical significance. No treatment-related changes in motor activity or behavior were observed. |
|
| |
Address |
Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1528-3593 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15136978 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1902 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shanahan, S. |
|
| |
Title |
Trailer loading stress in horses: behavioral and physiological effects of nonaversive training (TTEAM) |
Type |
Journal Article |
| |
Year |
2003 |
Publication |
Journal of Applied Animal Welfare Science : JAAWS |
Abbreviated Journal |
J Appl Anim Welf Sci |
|
| |
Volume |
6 |
Issue |
4 |
Pages |
263-274 |
|
| |
Keywords |
Animals; *Conditioning, Operant; *Escape Reaction; Female; Heart Rate; Horses/*psychology; Hydrocortisone/metabolism; Male; Saliva/metabolism; Stress/metabolism/prevention & control/*veterinary; *Transportation |
|
| |
Abstract |
Resistance in the horse to trailer loading is a common source of stress and injury to horses and their handlers. The objective of this study was to determine whether nonaversive training based on the Tellington-Touch Equine Awareness Method (TTEAM; Tellington-Jones &Bruns, 1988) would decrease loading time and reduce stress during loading for horses with a history of reluctance to load. Ten horses described by their owners as “problem loaders” were subjected to pretraining and posttraining assessments of loading. Each assessment involved two 7-min loading attempts during which heart rate and saliva cortisol were measured. The training consisted of six 30-min sessions over a 2-week period during which the horse and owner participated in basic leading exercises with obstacles simulating aspects of trailering. Assessment showed heart rate and saliva cortisol increased significantly during loading as compared to baseline (p <.001 and p <.05, respectively). Reassessment after training showed a decrease in loading time (p <.02), reduced heart rate during loading (p <.002), and reduced saliva cortisol as compared to pretraining assessments. Seven “good loaders” also were subject to loading assessment for physiological comparison. Increases in heart rate during loading were significantly higher in the good loaders (p <.001). Nonaversive training simulating aspects of loading may effectively reduce loading time and stress during loading for horses with a history of resistance to trailer loading. |
|
| |
Address |
shanahandvm@yahoo.ca |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1088-8705 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:14965781 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1903 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Visser, E.K.; Van Reenen, C.G.; Rundgren, M.; Zetterqvist, M.; Morgan, K.; Blokhuis, H.J. |
|
| |
Title |
Responses of horses in behavioural tests correlate with temperament assessed by riders |
Type |
Journal Article |
| |
Year |
2003 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
|
| |
Volume |
35 |
Issue |
2 |
Pages |
176-183 |
|
| |
Keywords |
Adult; Animals; *Behavior, Animal/physiology; Data Interpretation, Statistical; Female; *Handling (Psychology); Heart Rate/*physiology; Horses/physiology/*psychology; Humans; Male; Personality; Temperament/*physiology |
|
| |
Abstract |
REASONS FOR PERFORMING STUDY: Behavioural tests as well as observers' ratings have been used to study horses' temperament. However, the relationship between the ratings and the responses in behavioural tests has not yet been studied in detail. OBJECTIVES: The aim of the present study was to examine this relationship between ratings and responses. METHODS: Eighteen mature Swedish Warmblood horses were subjected to 2 behavioural tests, one relating to novelty (novel object test) and one to handling (handling test). Subsequently, 16 of these horses were ridden by 16 equally experienced students, having no former experience with the horses. Immediately after each ride, the students scored the horse for 10 temperamental traits using a line rating method. RESULTS: It was shown that for each temperamental trait all 16 riders agreed on the ranking of the horses (0.212<W<0.505, P < 0.001). CONCLUSIONS: Correlations between behavioural and heart rate variables in the behavioural tests revealed that horses with a high level of locomotion or much restlessness behaviour exhibited high mean heart rate and low heart rate variability. In particular, heart rate variables in the behavioural tests were found to correlate with riders' rating scores. Furthermore, the underlying components of the handling test, retrieved with a principal component analysis (PCA) correlated with riders' rating scores while the underlying components of the novel object test did not. POTENTIAL CLINICAL RELEVANCE: It is concluded that it is possible for a large panel of assessors to agree upon a horse's temperament and that objective measures from behavioural tests correlate significantly with temperamental traits assessed by a panel of assessors. |
|
| |
Address |
Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.163, NL-3508 TD Utrecht, The Netherlands |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0425-1644 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:12638795 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1906 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Momozawa, Y.; Ono, T.; Sato, F.; Kikusui, T.; Takeuchi, Y.; Mori, Y.; Kusunose, R. |
|
| |
Title |
Assessment of equine temperament by a questionnaire survey to caretakers and evaluation of its reliability by simultaneous behavior test |
Type |
Journal Article |
| |
Year |
2003 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
|
| |
Volume |
84 |
Issue |
2 |
Pages |
127-138 |
|
| |
Keywords |
Anxiety; Heart rate; Horse; Questionnaire; Temperament |
|
| |
Abstract |
We carried out a questionnaire survey of the caretakers, using 86 riding horses kept in the Equestrian Park, Tokyo (Japan Racing Association). The questionnaire survey used a 5-point scale and a 3-point scale to assess several caretakers' impressions of each horse's temperament, on the basis of the norm and the horse's tendencies in ordinary care and daily training. Factor analysis of the temperament scores obtained with the 5-point scale questionnaire revealed three mutually independent factors that we named “anxiety”, “novelty seeking” and “understanding”. In order to verify the reliability of this questionnaire survey, a balloon reactivity test was conducted using the same horses. Each horse was introduced into an unfamiliar indoor arena (7 mx12.5 mx3 m) in the center of which two balloons slowly revolved. The horses' responses were assessed by recording changes in their behavior and heart rate (HR) during the 5 min experimental period. By comparing the questionnaire survey and the balloon reactivity test, it was found that the horses evaluated as highly anxious by the caretakers tended to show greater HR increases and defecate more often during exposure to the balloon stimuli than did the other horses. Additionally, the horses assessed by caretakers to have problems with ordinary care and/or training showed greater increases of HR and frequency of defecation in the balloon reactivity test, and the horses assessed as having `a long adaptation time to unfamiliar objects' were found to be unwilling to touch the balloons. Thus, the horses' behavior during the balloon reactivity test was highly consistent with their temperament as determined by the questionnaire. These results suggest that the questionnaire survey would be an effective means to assess equine temperamental traits, especially those related to anxiety. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
1984 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rietmann, T.R.; Stuart, A.E.A.; Bernasconi, P.; Stauffacher, M.; Auer, J.A.; Weishaupt, M.A. |
|
| |
Title |
Assessment of mental stress in warmblood horses: heart rate variability in comparison to heart rate and selected behavioural parameters |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
|
| |
Volume |
88 |
Issue |
1-2 |
Pages |
121-136 |
|
| |
Keywords |
Horse; Hrv; Heart rate; Mental stress; Behaviour; Autonomic nervous system |
|
| |
Abstract |
The aim of the study was to investigate whether heart rate variability (HRV) could assess alterations of the autonomic nervous system (ANS) at different levels of excitement. The behavioural and physiological responses of 20 warmblood horses to a challenging ground exercise task were studied. Prior to the experiment, the horses were evaluated at rest and during forward walking (FW). The horses were then forced to move backwards continuously during 3 min according to a standardised protocol (BW1). Subsequently, the horses were exposed to two training sessions, after which the backward walking (BW2) was re-evaluated. Heart rate (HR) and HRV-parameters such as the standard deviation of the beat-to-beat intervals (SDRR), the low (LF; sympathetic tone) and high frequency (HF) component of HRV (HF; parasympathetic tone) and their ratio (LF/HF; index representing the sympatho-vagal balance) were sampled at rest, and during FW, BW1 and BW2. Stress-related behaviour during BW1 and BW2 was determined from video recordings. The results of the different evaluations were compared to each other. Compared to rest and FW, the first backward experiment induced a significant rise in HR, LF and LF/HF and a significant decrease of HF. SDRR decreased from both FW and rest with only the latter reaching significance. In BW2 after the training sessions, HR and the parameters of the sympathetic branch of the ANS (LF, LF/HF) were decreased and the vagal tone (HF) increased compared to BW1; all changes were significant. The duration of stress indicating behavioural patterns revealed also a significant decrease of excitement after the training, when backward walking did not differ from forward walking in any parameter. Correlations between HRV-parameters and stress indicating behaviour as well as HR were found. We conclude that the HRV-parameters LF and HF are valuable measures to quantify sympatho-vagal balance, which allows a more precise assessment of the responses of HR and SDRR to mental stress during low intensity exercise. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
314 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rietmann, T.R.; Stauffacher, M.; Bernasconi, P.; Auer, J.A.; Weishaupt, M.A. |
|
| |
Title |
The association between heart rate, heart rate variability, endocrine and behavioural pain measures in horses suffering from laminitis |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Journal of Veterinary Medicine. A, Physiology, Pathology, Clinical Medicine |
Abbreviated Journal |
J Vet Med A Physiol Pathol Clin Med |
|
| |
Volume |
51 |
Issue |
5 |
Pages |
218-225 |
|
| |
Keywords |
Animals; Anti-Inflammatory Agents, Non-Steroidal/administration & dosage; Autonomic Nervous System; Behavior, Animal; Electrophysiology/*methods; Endocrine System; Female; Heart Rate; Horse Diseases/blood/drug therapy/*physiopathology; Horses; Joint Diseases/physiopathology/*veterinary; Male; Pain/physiopathology/*veterinary; Pain Measurement/*veterinary; Predictive Value of Tests |
|
| |
Abstract |
The objective of this study was to compare the stress response of horses suffering from laminitis after short- and long-term treatment with the intent to evaluate power spectral analysis of heart rate variability (HRV) for pain monitoring. Data were collected from 19 horses with acute or chronic exacerbating laminitis without known primary disease before and after treatment with non-steroidal anti-inflammatory drugs (NSAID). Recordings were carried out the day after admission to the equine hospital. Measurements were repeated on day 7 of the treatment. The recorded parameters included a clinical orthopaedic index (OLPI: Obel-grade plus hoof tester score), frequency of weight-shifting between contralateral limbs, mean beat-to-beat interval (R-R) duration, standard deviation of continuous R-R intervals, low- (LF) and high-frequency (HF) components of HRV, sympatho-vagal balance (LF/HF), and plasma concentration of cortisol, adrenalin and noradrenalin. The LF represents mainly sympathetic influences on the heart whereas HF is mediated by the parasympathetic tone. Weight-shifting and OLPI decreased significantly with treatment. The LF normalized units (n.u.) decreased after NSAID from 60.41 +/- 21.42 to 51.12 +/- 19.81 and was 49.33 +/- 22.64 on day 7, whereas HF n.u. increased from 35.07 +/- 20.02 to 43.14 +/- 18.30 and was 45.98 +/- 23.00 on day 7. Hormone levels showed no tendency to change with treatment. The OLPI was only correlated with LF/HF, LF and HF (R = 0.57, 0.55 and -0.54 respectively). Significant negative correlations existed between HFn.u. and weight-shifting frequency (R = -0.37), HFn.u. and adrenalin (R = -0.47), and HFn.u. and noradrenalin (R = 0.33). The LFn.u. only correlated positively with adrenalin. Cortisol levels were poorly associated with the other parameters. Determination of the sympatho-vagal influences on cardiac function may offer complementary information for reliable assessment of pain and may represent a valuable alternative method to catecholamine measurements. |
|
| |
Address |
Equine Hospital, Faculty of Veterinary Medicine, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0931-184X |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15315700 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1899 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Waiblinger, S.; Menke, C.; Korff, J.; Bucher, A. |
|
| |
Title |
Previous handling and gentle interactions affect behaviour and heart rate of dairy cows during a veterinary procedure |
Type |
Journal Article |
| |
Year |
2004 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
|
| |
Volume |
85 |
Issue |
1-2 |
Pages |
31-42 |
|
| |
Keywords |
Human-animal relationship; Cattle; Handling; Stress; Heart rate; Welfare |
|
| |
Abstract |
Veterinary and management procedures often are aversive to the animals, resulting in physiological and behavioural stress reactions, which increase the risk of accidents and might lower performance. We investigated the effects of previous positive handling and of gentle interactions during the procedure on behaviour and heart rate in dairy cows during rectal palpation with sham insemination. Twenty cows were allocated randomly into two groups of 10 animals: handling, received additional positive handling over a period of four weeks by one person (handler); control, only routine handling by different caretakers. The week after the handling period, tests lasting 9 min, including 4 min rectal palpation, were carried out with each animal on four successive days in four situations in a balanced order: cow is alone during the test, with the handler, with an usual caretaker, or with an unknown person. Behaviour and heart rate were recorded. Previously handled animals had lower heart rate during tests (P<=0.05, n=19), kicked less when alone (P<=0.05, n=19) and tended to show less restless behaviour (P<=0.1, n=19). Cows were further calmed by gentle interactions during the test, but people differed remarkably. Cows showed less restless behaviour when gentled by the handler, both in the 4 min of rectal palpation and in the 9 min test period (each: P<=0.001, n=19). No significant stress reducing effect was found for the other two persons. In conclusion, stress reactions of cows during rectal palpation/insemination can be reduced by previous positive handling as well as by a person providing positive, gentle interactions during the procedure. The results underline the importance of positive, gentle interactions with the animals to enhance animal welfare and reduce the risk of accidents. They also show that people differ in the success to calm down the animals in aversive situations and indicate the need to investigate the characteristics responsible for the differences and identify the preconditions for a stress reducing effect in future research. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
4397 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nicol, C.J.; Adachi, M.; Akiyama, T.E.; Gonzalez, F.J. |
|
| |
Title |
PPARgamma in endothelial cells influences high fat diet-induced hypertension |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
American journal of hypertension : journal of the American Society of Hypertension |
Abbreviated Journal |
Am J Hypertens |
|
| |
Volume |
18 |
Issue |
4 Pt 1 |
Pages |
549-556 |
|
| |
Keywords |
Administration, Oral; Animals; Antihypertensive Agents/pharmacology; Blood Pressure/drug effects; Diabetes Mellitus, Type 2/physiopathology; Dietary Fats/*administration & dosage/pharmacology; Dose-Response Relationship, Drug; Endothelial Cells/*metabolism; Female; Heart Rate/drug effects; Hypertension/*etiology; Ligands; Male; Mice; Mice, Knockout; PPAR gamma/*metabolism; Sodium Chloride/administration & dosage/pharmacology; Thiazolidinediones/pharmacology |
|
| |
Abstract |
BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands improve human hypertension. However, the mechanism and site of this effect remains unknown, confounded by PPARgamma expression in many cell types, including endothelial cells (ECs). METHODS: To evaluate the vascular role of PPARgamma we used a conditional null mouse model. Specific disruption of PPARgamma in ECs was created by crossing Tie2-Cre+ transgenic (T2T+) and PPARgamma-floxed (fl/fl) mice to generate PPARgamma (fl/fl)T2T+ (PPARgamma E-null) mice. Conscious 8- to 12-week-old congenic PPARgamma (fl/fl)Cre- (wild type) and PPARgamma E-null mice were examined for changes in systolic blood pressure (BP) and heart rate (HR), untreated, after 2 months of salt-loading (drinking water), and after treatment for 3 months with high fat (HF) diet alone or supplemented during the last 2 weeks with rosiglitazone (3 mg/kg/d). RESULTS: Untreated PPARgamma E-nulls were phenotypically indistinguishable from wild-type littermates. However, compared to similarly treated wild types, HF-treated PPARgamma E-nulls had significantly elevated systolic BP not seen after normal diet or salt-loading. Despite sex-dependent baseline differences, salt-loaded and HF-treated PPARgamma E-nulls of either sex had significantly elevated HR versus wild types. Interestingly, rosiglitazone improved serum insulin levels, but not HF diet-induced hypertension, in PPARgamma E-null mice. CONCLUSIONS: These results suggest that PPARgamma in ECs not only is an important regulator of hypertension and HR under stressed conditions mimicking those arising in type 2 diabetics, but also mediates the antihypertensive effects of rosiglitazone. These data add evidence supporting a beneficial role for PPARgamma-specific ligands in the treatment of hypertension, and suggest therapeutic strategies targeting ECs may prove useful. |
|
| |
Address |
Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0895-7061 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15831367 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
69 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Christensen, J.W.; Keeling, L.J.; Nielsen, B.L. |
|
| |
Title |
Responses of horses to novel visual, olfactory and auditory stimuli |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
|
| |
Volume |
93 |
Issue |
1-2 |
Pages |
53-65 |
|
| |
Keywords |
Horses; Novelty responses; Fear; Behaviour; Heart rate |
|
| |
Abstract |
Responses of horses towards fear-eliciting stimuli can have important consequences for both human and horse safety. This experiment was designed to investigate behavioural and heart rate (HR) responses of horses to novel visual, auditory and olfactory stimuli. Twenty-four 2-year-old, previously unhandled, stallions were habituated to receive a food reward from a container in a test arena. Each horse was exposed to three 2 min tests in a balanced design where in addition to the feed container, either a traffic cone (visual test), white noise (auditory test) or eucalyptus oil applied to the inside of the container (olfactory test) were used as the novel stimuli. Compared to the control, less time was spent eating during all tests. There was no difference in locomotion activity in the different test situations, but presentation of the novel visual and auditory stimuli elicited significantly increased HR responses in the horses, compared to their response to the arena without novel stimuli (control), whereas there was no increase in HR response to the olfactory stimulus. However, during the olfactory test, the horses had an increased number of eating bouts and became more vigilant towards their surroundings, whereas during the visual and auditory tests, more time was spent alert towards the stimulus. The horses also took significantly more steps backwards in response to the auditory test. The heart rate responses correlated between tests and reflect a non-differentiated activation of the sympathetic nervous system, while the behavioural responses were linked to the type of stimulus. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
2256 |
|
| Permanent link to this record |
