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Author |
Houpt, T.R. |
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Title |
The physiological determination of meal size in pigs |
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Journal Article |
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Year |
1985 |
Publication |
The Proceedings of the Nutrition Society |
Abbreviated Journal |
Proc Nutr Soc |
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Volume |
44 |
Issue |
2 |
Pages |
323-330 |
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Keywords |
Animals; Appetite/physiology; Drinking; Duodenum/physiology; *Eating; Energy Intake; Food; Horses/physiology; Milk; Osmolar Concentration; Receptors, Cell Surface/physiology; Receptors, Cholecystokinin; Swine/*physiology; Time Factors |
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0029-6651 |
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PMID:2996010 |
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no |
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Call Number |
refbase @ user @ |
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53 |
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Author |
Crowell-Davis, S.L.; Houpt, K.A.; Carnevale, J. |
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Title |
Feeding and drinking behavior of mares and foals with free access to pasture and water |
Type |
Journal Article |
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Year |
1985 |
Publication |
Journal of animal science |
Abbreviated Journal |
J. Anim Sci. |
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Volume |
60 |
Issue |
4 |
Pages |
883-889 |
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Keywords |
Animals; *Drinking Behavior; *Feeding Behavior; Female; Horses/*physiology; Male; Poaceae; Seasons; Temperature; Time Factors |
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Abstract |
The feeding and drinking behavior of 11 mares and 15 foals living on pasture with free access to water was recorded during 2,340 15-min focal samples taken over 2 yr. Lactating mares on pasture spent about 70% of the day feeding. Foals began feeding on their first day of life. As they grew older, they spent progressively more time feeding, but still spent only 47 +/- 6% of the time feeding by 21 wk of age. Foals fed primarily during the early morning and evening. While grass formed the major proportion of the diet of both foals and mares, they also ate clay, humus, feces, bark, leaves and twigs. Almost all feeding by foals was done while their mothers were feeding. Movement to water sources was frequently, but not invariably, carried out by an entire herd. Frequency (P = .005) but not duration (P greater than .05) of drinking bouts by mares increased as the temperature increased. Frequency was greatest at 30 to 35 C, at which temperature mares drank once every 1.8 h. Frequency of drinking varied with the time of day (P less than .01), being rarest during the early morning (0500 to 0900 h eastern daylight time) and most frequent during the afternoon (1300 to 1700 h). Drinking by foals was very rare. The youngest age at which a foal was observed to drink was 3 wk, and 8 of 15 foals were never observed to drink before weaning. |
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0021-8812 |
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PMID:3988655 |
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refbase @ user @ |
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54 |
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Author |
Crowell-Davis, S.L.; Houpt, K.A. |
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Title |
Coprophagy by foals: effect of age and possible functions |
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Journal Article |
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Year |
1985 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
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17 |
Issue |
1 |
Pages |
17-19 |
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Keywords |
*Aging; Animals; *Coprophagia; Deoxycholic Acid/physiology; Female; Horse Diseases/*physiopathology; Horses; Humans; Male; Pheromones/physiology; Time Factors; Urination |
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Abstract |
In colts and fillies observed from birth to 24 weeks old, coprophagy occurred from Weeks 1 to 19. Its frequency was greatest during the first two months. Coprophagy was rarely observed in mares and stallions. Foals usually ate the faeces of their mother but were observed to eat their own and those of a stallion and another unrelated mare. Urination by the foal occurred before, during or after 26 per cent of the coprophagy incidents. It is hypothesised that foals may consume faeces in response to a maternal pheromone which signals the presence of deoxycholic acid or other acids which the foal may be deficient in and which it may require for gut immuno-competence myelination of the nervous system. Such a pheromone may also serve to accelerate growth and sexual maturation. Coprophagy may also provide nutrients and introduce normal bacterial flora to the gut. |
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0425-1644 |
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Notes |
PMID:4038939 |
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no |
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Call Number |
refbase @ user @ |
Serial |
55 |
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Author |
Sufit, E.; Houpt, K.A.; Sweeting, M. |
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Title |
Physiological stimuli of thirst and drinking patterns in ponies |
Type |
Journal Article |
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Year |
1985 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
17 |
Issue |
1 |
Pages |
12-16 |
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Keywords |
Animals; Blood Proteins/analysis; Drinking Behavior/drug effects/*physiology; Furosemide/pharmacology; Horses/*physiology; Male; Osmolar Concentration; Osmotic Pressure; Sodium Chloride/pharmacology; Thirst/drug effects/*physiology; Time Factors; Water Deprivation/physiology |
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The stimuli that elicit thirst were studied in four ponies. Nineteen hours of water deprivation produced an increase in plasma protein from 67 +/- 0.1 g/litre to 72 +/- 2 g/litre, a mean (+/- se) increase in plasma sodium from 139 +/- 3 to 145 +/- 2 mmol/litre and an increase in plasma osmolality from 297 +/- 1 to 306 +/- 2 mosmol/litre. Undeprived ponies drank 1.5 +/- 0.9 kg/30 mins; 19 h deprived ponies drank 10.2 +/- 2.5 kg/30 mins and corrected the deficits in plasma protein, plasma sodium and plasma osmolality as well as compensating for the water they would have drunk during the deprivation period. In order to determine if an increase in plasma osmolality would stimulate thirst, 250 ml of 15 per cent sodium chloride was infused intravenously. The ponies drank when osmolality increased 3 per cent and when plasma sodium rose from 136 +/- 3 mmol/litre to 143 +/- 3 mmol/litre. Ponies infused with 15 per cent sodium chloride drank 2.9 +/- 0.7 kg; those infused with 0.9 per cent sodium chloride drank 0.7 +/- 0.5 kg. In order to determine if a decrease in plasma volume would stimulate thirst, ponies were injected with 1 or 2 mg/kg bodyweight (bwt) frusemide. Plasma protein rose from 68 +/- 2 g/litre pre-injection to 75 +/- 2 g/litre 1 h after 1 mg/kg bwt frusemide and to 81 +/- 1 g/litre 1 h after 2 mg/kg bwt frusemide.(ABSTRACT TRUNCATED AT 250 WORDS) |
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0425-1644 |
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Notes |
PMID:3979367 |
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no |
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Call Number |
refbase @ user @ |
Serial |
56 |
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Author |
Houpt, K.A.; Parsons, M.S.; Hintz, H.F. |
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Title |
Learning ability of orphan foals, of normal foals and of their mothers |
Type |
Journal Article |
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Year |
1982 |
Publication |
Journal of animal science |
Abbreviated Journal |
J. Anim Sci. |
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Volume |
55 |
Issue |
5 |
Pages |
1027-1032 |
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Keywords |
Age Factors; Animals; Body Weight; Dominance-Subordination; Female; Horses/*physiology; *Learning; *Maternal Deprivation; Mothers/*psychology |
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Abstract |
The maze learning ability of six pony foals that had been weaned at birth was compared to that of six foals reared normally. The foals' learning ability was also compared to their mothers' learning ability at the same task; the correct turn in a single choice point maze. The maze learning test was conducted when the foals were 6 to 8 mo old and after the mothered foals had been weaned. There was no significant difference between the ability of orphaned (weaned at birth) and mothered foals in their ability to learn to turn left (6 +/- .7 and 5.1 +/- .1 trials, respectively) or to learn the reversal, to turn right (6.7 +/- .6 and 6.2 +/- .6 trials, respectively). The orphan foals spent significantly more time in the maze in their first exposure to it than the mothered foals (184 +/- 42 vs 55 +/- 15 s. Mann Whitney U = 7, P less than .05). The mothers of the foals (n = 11) learned to turn left as rapidly as the foals (5.9 +/- .7 trials), but they were slower to learn to turn right (9.8 +/- 1.4 vs 6.4 +/- .4 trials, Mann Whitney U = 33, P less than .05), indicating that the younger horses learned more rapidly. There was no correlation between the trials to criteria of the mare and those of her foal, but there was a significant negative correlation between rank in trials to criteria and age (r = -65, P less than .05) when data from the mare and foal trials were combined. The dominance hierarchy of the mares was determined using a paired feeding test in which two horses competed for one bucket of feed. Although there was no correlation between rank in the hierarchy and maze learning ability, there was a correlation between body weight and rank in the hierarchy (r = .7, P less than .05). This may indicate either that heavier horses are likely to be dominant or that horses high in dominance gain more weight. Maternal deprivation did not appear to seriously retard learning of a simple maze by foals, although the orphans moved more slowly initially. The lack of maternal influence on learning is also reflected in the lack of correlation between the mare's learning ability and that of her foal. Young horses appear to learn more rapidly than older horses. |
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0021-8812 |
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Notes |
PMID:7174546 |
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no |
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Call Number |
refbase @ user @ |
Serial |
58 |
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Author |
Brown, R.F.; Houpt, K.A.; Schryver, H.F. |
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Title |
Stimulation of food intake in horses by diazepam and promazine |
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Journal Article |
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Year |
1976 |
Publication |
Pharmacology, biochemistry, and behavior |
Abbreviated Journal |
Pharmacol Biochem Behav |
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Volume |
5 |
Issue |
4 |
Pages |
495-497 |
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Keywords |
Age Factors; Animals; Diazepam/*pharmacology; Diet; Feeding Behavior/*drug effects; Female; Horses/*physiology; Male; Promazine/*pharmacology; Stimulation, Chemical |
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Abstract |
In two adult horses doses of 0.02-0.03 mg/kg diazepam, intravenously, increased 1 hr intake 54-75% above control levels. Intake was stimulated when the diet was a high grain, calorically dense one and also when the diet was a high fiber, calorically dilute one. Two young rapidly growing weanling horses showed an even more pronounced stimulation of intake. Following diazepam 1 hr intake was increased 105-240% above control lelvels. Promazine at a dose of 0.5 mg/kg also stimulated intake in adult horses, but not as markedly as did diazepam. A transquilizer and a neuroleptic appear to have a stimulatory eff upon short-term intake in horses. |
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0091-3057 |
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PMID:1005496 |
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no |
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refbase @ user @ |
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60 |
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Author |
Dixon, G.; Green, L.E.; Nicol, C.J. |
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Title |
Effect of diet change on the behavior of chicks of an egg-laying strain |
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Journal Article |
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Year |
2006 |
Publication |
Journal of applied animal welfare science : JAAWS |
Abbreviated Journal |
J Appl Anim Welf Sci |
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Volume |
9 |
Issue |
1 |
Pages |
41-58 |
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Keywords |
*Animal Feed; *Animal Nutrition Physiology; Animals; Behavior, Animal/*physiology; Chickens/*physiology; Crowding; Feeding Behavior/*physiology; Female; Food Preferences/physiology; Oviposition; Random Allocation; Taste |
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Injurious pecking has serious welfare consequences in flocks of hens kept for egg laying, especially when loose-housed. Frequent diet change is a significant risk for injurious pecking; how the mechanics of diet change influence pecking behavior is unknown. This study investigated the effect of diet change on the behavior of chicks from a laying strain. The study included a 3-week familiarity phase: 18 chick pairs received unflavored feed (Experiment 1); 18 pairs received orange oil-flavored (Experiment 2). All chicks participated in a dietary preference test (P); a diet change (DC); or a control group (C), 6 scenarios. All P chicks preferred unflavored feed. In Experiment 1, DC involved change from unflavored to orange-flavored; Experiment 2, orange- flavored to unflavored. Compared with controls, Experiment 2 DC chicks exhibited few behavioral differences; Experiment 1 DC chicks exhibited increased behavioral event rates on Days 1 and 7. They pecked significantly longer at their environment; by Day 7, they showed significantly more beak activity. There was little evidence of dietary neophobia. Change from more preferred to less preferred feed led to increased activity and redirected pecking behavior. |
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School of Veterinary Science, University of Bristol, England |
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ISSN |
1088-8705 |
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PMID:16649950 |
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no |
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Call Number |
refbase @ user @ |
Serial |
64 |
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Author |
Nicol, C.J.; Brown, S.N.; Glen, E.; Pope, S.J.; Short, F.J.; Warriss, P.D.; Zimmerman, P.H.; Wilkins, L.J. |
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Title |
Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries |
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Journal Article |
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Year |
2006 |
Publication |
British poultry science |
Abbreviated Journal |
Br Poult Sci |
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Volume |
47 |
Issue |
2 |
Pages |
135-146 |
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Keywords |
Animal Husbandry/*methods; *Animal Welfare; Animals; Body Constitution/*physiology; Chickens/*physiology; Crowding; Feathers; Female; *Housing, Animal/standards; Mortality; Organ Size; Oviposition/physiology; Population Density; Population Dynamics; Random Allocation |
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Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay. |
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Address |
School of Veterinary Science, University of Bristol, Langford House, Langford BS40 5DU and ADAS Gleadthorpe, Meden Vale, Mansfield, Notts NG20 9PF, England. c.j.nicol@bristol.ac.uk |
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0007-1668 |
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Notes |
PMID:16641024 |
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no |
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Call Number |
refbase @ user @ |
Serial |
65 |
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Author |
Cheung, C.; Akiyama, T.E.; Ward, J.M.; Nicol, C.J.; Feigenbaum, L.; Vinson, C.; Gonzalez, F.J. |
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Title |
Diminished hepatocellular proliferation in mice humanized for the nuclear receptor peroxisome proliferator-activated receptor alpha |
Type |
Journal Article |
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Year |
2004 |
Publication |
Cancer research |
Abbreviated Journal |
Cancer Res |
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Volume |
64 |
Issue |
11 |
Pages |
3849-3854 |
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Keywords |
Animals; Anticholesteremic Agents/pharmacology; Carcinogens/pharmacology; Cell Division; DNA Replication/drug effects; Fatty Acids/metabolism; Hepatocytes/cytology/drug effects/metabolism/*physiology; Humans; Mice; Mice, Transgenic; Oxidation-Reduction; Peroxisome Proliferators/pharmacology; Pyrimidines/pharmacology; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Species Specificity; Transcription Factors/genetics/*physiology |
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Abstract |
Lipid-lowering fibrate drugs function as agonists for the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha). Sustained activation of PPARalpha leads to the development of liver tumors in rats and mice. However, humans appear to be resistant to the induction of peroxisome proliferation and the development of liver cancer by fibrate drugs. The molecular basis of this species difference is not known. To examine the mechanism determining species differences in peroxisome proliferator response between mice and humans, a PPARalpha-humanized mouse line was generated in which the human PPARalpha was expressed in liver under control of the tetracycline responsive regulatory system. The PPARalpha-humanized and wild-type mice responded to treatment with the potent PPARalpha ligand Wy-14643 as revealed by induction of genes encoding peroxisomal and mitochondrial fatty acid metabolizing enzymes and resultant decrease of serum triglycerides. However, surprisingly, only the wild-type mice and not the PPARalpha-humanized mice exhibited hepatocellular proliferation as revealed by elevation of cell cycle control genes, increased incorporation of 5-bromo-2'-deoxyuridine into hepatocyte nuclei, and hepatomegaly. These studies establish that following ligand activation, the PPARalpha-mediated pathways controlling lipid metabolism are independent from those controlling the cell proliferation pathways. These findings also suggest that structural differences between human and mouse PPARalpha are responsible for the differential susceptibility to the development of hepatocarcinomas observed after treatment with fibrates. The PPARalpha-humanized mice should serve as models for use in drug development and human risk assessment and to determine the mechanism of hepatocarcinogenesis of peroxisome proliferators. |
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Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
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0008-5472 |
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Notes |
PMID:15172993 |
Approved |
no |
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Call Number |
refbase @ user @ |
Serial |
74 |
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Author |
Nicol, C.J.; Yoon, M.; Ward, J.M.; Yamashita, M.; Fukamachi, K.; Peters, J.M.; Gonzalez, F.J. |
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Title |
PPARgamma influences susceptibility to DMBA-induced mammary, ovarian and skin carcinogenesis |
Type |
Journal Article |
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Year |
2004 |
Publication |
Carcinogenesis |
Abbreviated Journal |
Carcinogenesis |
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Volume |
25 |
Issue |
9 |
Pages |
1747-1755 |
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Keywords |
9,10-Dimethyl-1,2-benzanthracene/*toxicity; Animals; DNA Primers/chemistry; Disease Susceptibility; Female; Heterozygote; Humans; Mammary Neoplasms, Experimental/chemically induced/*pathology; Mice; Ovarian Neoplasms/chemically induced/*pathology; RNA, Messenger/genetics/metabolism; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Reverse Transcriptase Polymerase Chain Reaction; Skin Neoplasms/chemically induced/*pathology; Survival Rate; Transcription Factors/genetics/*physiology; Zinc Fingers |
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Abstract |
Peroxisome proliferator-activated receptor gamma (PPARgamma), a member of the nuclear receptor superfamily, plays a role in adipocyte differentiation, type II diabetes, macrophage response to inflammation and is suggested to influence carcinogen-induced colon cancer. Studies done in vitro and in vivo also revealed that PPARgamma ligands might promote differentiation and/or regression of mammary tumors. To directly evaluate the role of PPARgamma in mammary carcinogenesis, PPARgamma wild-type (+/+) or heterozygous (+/-) mice were administered 1 mg 7,12-dimethylbenz[a]anthracene (DMBA) by gavage once a week for 6 weeks and followed for a total of 25 weeks. Compared with congenic PPARgamma(+/+) littermate controls, PPARgamma(+/-) mice had early evidence for increased susceptibility to DMBA-mediated carcinogenesis based on a 1.6-fold increase in the percentage of mice with skin papillomas, as well as a 1.7-fold increase in the numbers of skin papillomas per mouse (P < 0.05). Similarly, PPARgamma(+/-) mice also had a 1.5-fold decreased survival rate (P = 0.059), and a 1.7-fold increased incidence of total tumors per mouse (P < 0.01). Moreover, PPARgamma(+/-) mice had an almost 3-fold increase in mammary adenocarcinomas (P < 0.05), an over 3-fold increase in ovarian granulosa cell carcinomas (P < 0.05), an over 3-fold increase in malignant tumors (P < 0.02) and a 4.6-fold increase in metastatic incidence. These results are the first to demonstrate an increased susceptibility in vivo of PPARgamma haploinsufficiency to DMBA-mediated carcinogenesis and suggest that PPARgamma may act as a tumor modifier of skin, ovarian and breast cancers. The data also support evidence suggesting a beneficial role for PPARgamma-specific ligands in the chemoprevention of mammary, ovarian and skin carcinogenesis. |
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Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA |
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English |
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0143-3334 |
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PMID:15073042 |
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76 |
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