Strain, age and sex differences in the release of vasopressin from the pituitary: a study in the spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rat.
The basal and depolarization-induced arginine-vasopressin (AVP) release from intact pituitaries of SHR and WKY rats was studied in vitro in a perfusion chamber. Differences associated to strain, sex and two age periods (pre-adult: 25-30 days of age; adult: 60-70 days of age) were assessed. The results show an enhanced AVP release in the adult male as well as female SHR compared to the WKY rat. The stimulated AVP release was also significantly higher in the preadult male SHR and indicated in preadult females SHR. No differences associated to strain in basal AVP release were detected at the age interval 25-30 days. The response to muscimol was increased in preadult female and male SHR rats compared to the WKY animals. It is concluded that the augmented depolarization-induced AVP release and sensitivity to muscimol in the SHR is not related to sex, and no apparent change in this pattern was associated to the transition between the juvenile and adult condition.
Magnusson
K
K
Department of Medical Pharmacology, Uppsala University, Sweden.
Meyerson
B J
BJ
D000367:Age Factors; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism*; D003864:Depression, Chemical; D005260:Female; D018755:GABA Agonists / Q000494:pharmacology; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D010904:Pituitary Gland, Posterior / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011918:Rats, Inbred SHR / Q000502:physiology*; D011921:Rats, Inbred WKY / Q000502:physiology*; D012636:Secretory Rate / Q000187:drug effects; D012727:Sex Characteristics
D018755:GABA Agonists; D001127:Arginine Vasopressin; D009118:Muscimol