Serum inhibin A, inhibin B, and pro-alphaC levels are altered after surgically or pharmacologically induced menopause.
OBJECTIVE
To evaluate the course of changes in serum inhibin A, inhibin B, and pro-alphaC levels in women with surgically or pharmacologically induced menopause.


METHODS
Longitudinal study.


METHODS
Academic Health Center of Siena, Siena, Italy.


METHODS
Four groups of women were studied: [1] surgical menopause including bilateral oophorectomy (n = 15), [2] amenorrhea induced by GnRH-analogue for treatment of endometriosis (n = 13), [3] amenorrhea induced by antineoplastic chemotherapy before (n = 15) and after chemotherapy (n = 13), and [4] control physiological menopause (n = 67).


METHODS
Collection of blood specimens.


METHODS
Serum inhibin A, inhibin B, and pro-alphaC concentrations were measured by using specific two-site ELISAs.


RESULTS
Following oophorectomy, serum inhibin A, inhibin B, and pro-alphaC levels were decreased on the first postoperative day; on the fifth postoperative day they were still significantly reduced. Women with amenorrhea induced by GnRH-analogue treatment exhibited serum inhibin A and pro-alphaC levels that were significantly higher than those observed in physiological menopause. Patients undergoing antineoplastic chemotherapy had higher serum inhibin A levels than those in physiological menopause, whereas inhibin B and pro-alphaC levels did not differ. During the course of chemotherapy, median serum inhibin A concentrations were similar to those of patients evaluated after the suspension of treatment. In postmenopause, inhibin A, and inhibin B levels were low, whereas levels of pro-alphaC were still detectable.


CONCLUSIONS
Circulating levels of inhibin A, inhibin B, and pro-alphaC are reduced after oophorectomy. Women with amenorrhea induced by GnRH-analogue treatment or by antineoplastic chemotherapy still produce inhibin A and pro-alphaC. This probably reflects a residual ovarian function and hormone synthesis. Therefore, the ovary may be a source of pro-alphaC after menopause; significant amounts of pro-alphaC are present in circulation after natural menopause, but not after oophorectomy.
Cobellis
Luigi
L
Chair of Obstetrics and Gynecology, University of Siena, Siena, Italy.
Luisi
Stefano
S
Pezzani
Ilaria
I
Reis
Fernando M
FM
De Leo
Vincenzo
V
Petraglia
Felice
F
D000568:Amenorrhea / Q000139:chemically induced*; D000970:Antineoplastic Agents / Q000009:adverse effects; D004715:Endometriosis / Q000188:drug therapy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives; D006801:Humans; D007265:Inhibins / Q000097:blood*; D007700:Kinetics; D008137:Longitudinal Studies; D008593:Menopause / Q000097:blood*; D008875:Middle Aged; D010052:Ovariectomy; D017698:Postmenopause / Q000097:blood; D011184:Postoperative Period; D011498:Protein Precursors / Q000097:blood*
D000970:Antineoplastic Agents; D011498:Protein Precursors; C422362:inhibin A; C422364:inhibin B; C095971:inhibin-alpha subunit precursor; D007987:Gonadotropin-Releasing Hormone; D007265:Inhibins