Salma Aslam Kundi, Saleem Wazir, Saleem Afzal, Naeema Afzal, Iftikhar Qayum, Mary L. Forsling


Background: The vasopressin (AVP) response to hypovolemia has been compared in intact and
chemically castrated rats. This functional ovariectomy was done to confirm the findings in surgical
ovariectomy 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 consecutive
cycles. The ten control rats were given sub-cutaneous puncture only whereas the experimental
were given Zoladex implant. On the fifteenth day all the rats were given intra-peitoneal injection
of poly-ehylene glycol. All the rats were de-capitated after an hour. Results: The uterine weight
was significantly decreased in experimental group. The plasma AVP level was also significantly
decreased in the experimental group. The pituitary AVP level was significantly increased in the
experimental group. Conclusion: The chemical castration effected the AVP secretion, this proves
that the sex steroids modulate the release of AVP secretion inspite of hypo-volemic challenge.
Keywords: Zoladex, Hypovolemia, Vasopressin

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