Effect of XXXX on gonadotropin secretion before and after @entity251 in @entity252 .

@entity1 @entity3033 @entity251 @entity252 @entity1510 @entity3696
A study was performed on eight subjects with @entity252 to assess the relation between gonadal hormones and opioid inhibition of gonadotropin secretion through comparison of their gonadotropin response to @entity1510 ( @entity3696 ) (0.3 mg/kg; 1/3 bolus iv. at time 0 and 2/3 iv. for 120 min) before and after @entity3033 (TP) 100 mg/day im. for 5 days. Under basal conditions, NAL failed to induce a significant change in LH levels. After TP, however, despite unchanged basal LH levels (mean +/- S.E.M.: 27.0 +/- 3.4 vs 21.2 +/- 3.21 microU/ml), LH significantly increased in response to NAL. FSH did not respond to NAL either before or after TP administration, though FSH levels were significantly reduced by TP. These findings suggest that in @entity1 , as in animals, gonadal hormones regulate opioid inhibition of LH secretion. The negative feedback of @entity251 and its ability to activate opioid inhibiting tone may be dissociated, in keeping with the view that gonadal hormones control gonadotropin secretion through the activation of distinct, albeit concomitant, mechanisms.
