Modulatory role of estrogens and progestins on growth hormone episodic release in women with hypothalamic amenorrhea.
OBJECTIVE
To define the characteristics of spontaneous GH episodic secretion and the modulatory role of gonadal steroids in patients with hypothalamic amenorrhea associated with weight loss.


METHODS
Women were studied for 8 hours, sampling every 10 minutes, and plasma GH levels were measured by RIA.


METHODS
Fifteen patients with weight-loss-related amenorrhea were studied in baseline conditions. Five out of 15 patients underwent two cycles of hormonal replacement therapy with E2 patches (100 micrograms every 3 days for 24 days) and medroxyprogesterone acetate (MPA) (10 mg/d, from day 12 to day 24). On the second cycle of therapy, the pulsatility study was repeated twice: after only estrogen (day 11) and after E2 plus progestin (day 22). Four normally cycling women were studied as a reference group during midfollicular and midluteal phases.


RESULTS
Amenorrheic patients showed mean plasma GH levels similar to healthy women during the follicular phase but significantly lower than those observed during the luteal phase. GH pulse frequency was higher in patients than in controls, whereas pulse amplitude was comparable with the follicular phase but lower during the luteal phase. During the hormonal replacement therapy, when only E2 was administered, GH pulse frequency decreased, whereas GH integrated plasma concentrations and GH pulse amplitude increased significantly. After MPA and E2 administration, GH pulse amplitude and GH plasma levels decreased, which was similar to pretreatment condition.


CONCLUSIONS
The present study demonstrated that in amenorrhea associated with weight loss the frequency of GH episodic release is significantly higher than in normally cycling women. Moreover, a different modulatory role of estrogen (increased amplitude) and P (decreased amplitude) on the episodic release of GH in amenorrheic women undergoing a replacement treatment was shown by the present data.
Genazzani
A D
AD
Department of Obstetrics and Gynecology, University of Modena, Italy.
Petraglia
F
F
Volpogni
C
C
Gastaldi
M
M
Pianazzi
F
F
Montanini
V
V
Genazzani
A R
AR
D000568:Amenorrhea / Q000188:drug therapy / Q000378:metabolism*; D004359:Drug Therapy, Combination; D004958:Estradiol / Q000627:therapeutic use; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000502:physiology*; D005260:Female; D005498:Follicular Phase; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D007027:Hypothalamic Diseases / Q000188:drug therapy / Q000378:metabolism*; D008183:Luteal Phase; D017258:Medroxyprogesterone Acetate / Q000627:therapeutic use; D011372:Progestins / Q000502:physiology*
D004967:Estrogens; D011372:Progestins; D004958:Estradiol; D013006:Growth Hormone; D017258:Medroxyprogesterone Acetate