Umar Ali Khan, Mansoor Ali Khan, Aamir Ali Khan


This study was carried out to see the response of ovariectomy in adult female rats as
determined by rat Luteinising Hormone (rLH) Radioimmunoassay (R1A). Animals were
divided in two groups. Group I (control, n=6) were sham ovariectomised and group II
(experimented, n=4) were ovariectomised. Next day at 1400 hours’ rats were sacrificed and
their plasma was collected for rLH, RIA. It was observed that there was highly significant
increase in plasma rLH (P<0.001) in experimental group as compared to controls. Also the
increase in the weights of hypothalamus and anterior pituitary of experimental group was
highly significant (P<0.001) as compared to controls. This shows that this rise in plasma
rLH and weights of hypothalamus and anterior pituitary was due to loss of negative feedback
effect of ovarian steroids.

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