RELEASE OF VASOPRESSIN DURING SUPPRESSION OF OESTROUS CYCLE IN RAT BY ZOLADEX AND HYPOVOLEMIC CHALLENGE
AbstractBackground: The vasopressin (AVP) response to hypovolemia has been compared in intact andchemically castrated rats. This functional ovariectomy was done to confirm the findings in surgicalovariectomy of how gonadal steroids modulate the release of AVP under hypo-volemic challenge.Methods: Twenty female Sprague Dawley rats were checked for oestrous over two consecutivecycles. The ten control rats were given sub-cutaneous puncture only whereas the experimentalwere given Zoladex implant. On the fifteenth day all the rats were given intra-peitoneal injectionof poly-ehylene glycol. All the rats were de-capitated after an hour. Results: The uterine weightwas significantly decreased in experimental group. The plasma AVP level was also significantlydecreased in the experimental group. The pituitary AVP level was significantly increased in theexperimental group. Conclusion: The chemical castration effected the AVP secretion, this provesthat the sex steroids modulate the release of AVP secretion inspite of hypo-volemic challenge.Keywords: Zoladex, Hypovolemia, Vasopressin
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