title: Episodic luteinizing hormone release in hyperprolactinemic women.
abstract: Episodic luteinizing hormone (LH) secretion was studied in 16 hyperprolactinemic women (microprolactinoma, 12; idiopathic, 4) with amenorrhea of 1.4 to 7 years' duration. Blood samples obtained through an indwelling venous catheter at 20-minute intervals over 5 hours were assayed for LH, follicle-stimulating hormone (FSH), prolactin (PRL), and estrogen (E) (selected samples). LH pulse patterns were divided arbitrarily into high-amplitude release (LH pulse greater than 10 mIU/ml) (n = 7), low-amplitude release (LH pulse less than 10 mIU/ml (n = 6), and no release (n = 3). Mean pulse frequencies in women with high-amplitude and low-amplitude release were 2.4 +/- 0.3 (mean +/- standard error) and 1.3 +/- 0.2 pulses/5 hours and differed significantly (P greater than 0.02), whereas mean percentages of secretory increment were 155% and 62%, respectively. Mean LH concentrations in the high-amplitude (18.0 +/- 0.8 mIU/ml), low-amplitude (13.2 +/- 0.6 mIU/ml), and no-pulse groups (7.5 +/- 0.2 mIU/ml) differed significantly (P greater than 0.02). Despite the different pulse patterns, mean serum FSH, PRL, and total E concentrations were similar. The lack of episodic LH release and/or low infrequent LH release could account for the absence of cyclic hypothalamic pituitary ovarian function, although other mechanism(s) may be operative in women with augmented LH secretory pulses.
authors.forename: R H
authors.initials: RH
authors.lastname: Wiebe
authors.forename: S
authors.initials: S
authors.lastname: Handwerger
authors.forename: M
authors.initials: M
authors.lastname: Soules
mesh_terms: D000328:Adult; D000568:Amenorrhea / Q000097:blood / Q000209:etiology; D004967:Estrogens / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D006966:Hyperprolactinemia / Q000097:blood* / Q000150:complications; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D011388:Prolactin / Q000097:blood; D013997:Time Factors
chemical_list: D004967:Estrogens; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone