[The mechanism of induction of ovulation by bromocriptine in euprolactinemic anovulation--the role of occult hyperprolactinemia in anovulation].
It has been well documented that ovulation was induced by Bromocriptine treatment in euprolactinemic anovulation. The present study has been carried out to clarify the underlying mechanism. 28 patients with euprolactinemia (PRL less than 25 ng/ml) were treated with a 5 mg daily administration of Bromocriptine. Ovulation was induced in 13 cases, which were determined by their BBT charts. In the ovulated cases, PRL secreting capacities were increased, determined by TRH administration. On the other hand, PRL secreting capacities were normal in the anovulated cases. The studies of the circadian secretion of PRL revealed that a nocturnal hyperprolactinemic state occurred for several hours in the ovulated cases, which was not seen in the anovulated cases. From these results, the mechanism of induction of ovulation by Bromocriptine in euprolactinemic anovulation exists on the suppression of the increased PRL secreting capacity, which may be related to the occulted hyperprolactinemia at night. Ovulated cases by Bromocriptine are seemingly euprolactinemia, but in truth they may be a kind of hyperprolactinemia.
D000328:Adult; D000858:Anovulation / Q000097:blood* / Q000188:drug therapy; D001971:Bromocriptine / Q000494:pharmacology* / Q000627:therapeutic use; D002940:Circadian Rhythm; D003864:Depression, Chemical; D005260:Female; D006801:Humans; D010062:Ovulation Induction; D011388:Prolactin / Q000097:blood / Q000378:metabolism*
D001971:Bromocriptine; D011388:Prolactin