Evidence of altered dopaminergic modulation of Prl, LH and TSH secretion in patients with normoprolactinaemic amenorrhoea.
Basal plasma concentrations of Prl, LH, FSH, GH, TSH, T3, T4, resin T3 uptake ( RT3U ), and oestradiol as well as hormone responses to iv metoclopramide (MTC) were investigated in 16 consecutive patients with normoprolactinaemic, normogonadotrophic amenorrhoea. The control group consisted of 17 normal menstruating women between day 3 and 6 of the menstrual cycle. The mean age of the amenorrhoeic patients was 24.0 years (range 19 to 34) and the mean duration of amenorrhoea was 31 months (range 12 to 60). Amenorrhoeic patients had significantly (P less than 0.05) lower basal levels of LH, oestradiol and RT3U , whereas other hormone levels were similar in the two groups. Plasma Prl and TSH concentrations rose significantly (P less than 0.05) after the administration of MTC in the two groups. A significant positive correlation (r = 0.69 P less than 0.01) was found between the TSH response to MTC and basal TSH levels in controls, but not in amenorrhoeic patients. Plasma LH levels increased significantly (P less than 0.05) in amenorrhoeic patients, but not in controls. The Prl and TSH responses to MTC were significantly (P less than 0.001) lower in amenorrhoeic patients than in normal women. In amenorrhoeic patients none of the hormonal parameters correlated significantly (P greater than 0.05) with the percentage of ideal body weight. It is concluded that the hormonal changes in amenorrhoeic patients may in part be caused by a raised dopaminergic activity leading to a depression of central ovulatory mechanisms.
D000328:Adult; D000568:Amenorrhea / Q000097:blood / Q000503:physiopathology*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D007031:Hypothalamus / Q000187:drug effects; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D008787:Metoclopramide / Q000494:pharmacology*; D011388:Prolactin / Q000097:blood / Q000378:metabolism*; D011954:Receptors, Dopamine / Q000187:drug effects*; D013963:Thyroid Hormones / Q000097:blood; D013972:Thyrotropin / Q000378:metabolism*
D011954:Receptors, Dopamine; D013963:Thyroid Hormones; D004958:Estradiol; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D013006:Growth Hormone; D008787:Metoclopramide