• Umar Ali Khan
  • Mansoor Ali Khan
  • Aamir Ali Khan


This study was carried out to see the response of ovariectomy in adult female rats asdetermined by rat Luteinising Hormone (rLH) Radioimmunoassay (R1A). Animals weredivided 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 andtheir plasma was collected for rLH, RIA. It was observed that there was highly significantincrease in plasma rLH (P<0.001) in experimental group as compared to controls. Also theincrease in the weights of hypothalamus and anterior pituitary of experimental group washighly significant (P<0.001) as compared to controls. This shows that this rise in plasmarLH and weights of hypothalamus and anterior pituitary was due to loss of negative feedbackeffect of ovarian steroids.


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