Prostaglandin-dependent c-Fos expression in the median preoptic nucleus of pigs subjected to restraint: correlation with hyperthermia.
Restraint using a nose snare activates the hypothalamo-pituitary-adrenocortical axis and induces c-Fos expression in the paraventricular hypothalamus in the pre-pubertal pig; this procedure also induces hyperthermia in pigs. To investigate the neural mechanisms involved in this thermoregulatory response, c-Fos protein was quantified in the forebrains of pigs snared for 15 min (n = 5), injected with saline vehicle via an i.v. catheter (controls, n = 4) or treated with the cyclooxygenase inhibitor, indomethacin (2 mg/kg i.v.), prior to a 15 min period of snaring (n = 3). There were few c-Fos immunopositive nuclei in the median preoptic nucleus of non-stressed animals. By contrast, c-Fos expression in this region was enhanced by snaring (P < 0.001) and this response was markedly reduced (P < 0.002) by indomethacin. The results suggest that restraint induces a prostaglandin-mediated increase in core temperature (stress hyperthermia) in the growing pig that involves the activation of preoptic thermoregulatory neurons.
Vellucci
S V
SV
MAFF Welfare and Behaviour Laboratory, Department of Neurobiology, Babraham Institute, Cambridge, UK.
Parrott
R F
RF
D000818:Animals; D001833:Body Temperature Regulation / Q000187:drug effects / Q000502:physiology*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D005334:Fever / Q000503:physiopathology; D005786:Gene Expression Regulation / Q000502:physiology*; D007150:Immunohistochemistry; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D011301:Preoptic Area / Q000378:metabolism*; D011453:Prostaglandins / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis* / Q000235:genetics; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000378:metabolism*; D013552:Swine
D016861:Cyclooxygenase Inhibitors; D011453:Prostaglandins; D016760:Proto-Oncogene Proteins c-fos; D007213:Indomethacin