In vitro stimulation of cumulus-cell expansion by human cord serum in mouse oocyte-cumulus complexes.
OBJECTIVE
The aim of this study was to test whether human cord serum (HCS) containing gonadotropins has an effect on the expansion of oocyte-cumulus complexes (OCCs).


METHODS
The concentration of follicle stimulating hormone (FSH) and luteinizing hormone (LH) was measured in HCS by radioimmunoassay (RIA). After short-term culture (4 hr) with or without OCCs, medium containing 0.4% bovine serum albumin (BSA) as control or 10% HCS was collected and analyzed for its concentration of estradiol, progesterone, and testosterone.


RESULTS
The FSH concentration was at the basal level, but the LH level was as high as 142.4 mIU/ml in both natured and denatured serum. Undetectable levels of steroids were observed in control media with or without OCCs. In contrast, a moderate amount of steroid hormones was detected in culture medium containing HCS. OCCs secreted a minute amount of steroid hormones in response to HCS. Similar patterns of cumulus expansion were observable by treatment with HCS, human chorionic gonadotropin (hCG), or HCS plus hCG after 4, 8, or 22 hr of culture. However, no cumulus expansion was observed in controls.


CONCLUSIONS
These results suggest that LH in HCS induces cumulus expansion but does not affect the secretion of steroid hormones by OCCs during culture.
Lee
Y I
YI
Department of Obstetrics and Gynecology, Chonnam University Medical School, Kwangju, Korea.
Park
H J
HJ
Kwon
Y S
YS
D000818:Animals; D002478:Cells, Cultured; D004958:Estradiol / Q000097:blood; D005260:Female; D005312:Fetal Blood / Q000737:chemistry / Q000502:physiology*; D005640:Follicle Stimulating Hormone / Q000097:blood; D006062:Gonadotropins / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D051379:Mice; D008813:Mice, Inbred ICR; D009865:Oocytes / Q000254:growth & development*; D006080:Ovarian Follicle / Q000166:cytology*; D011374:Progesterone / Q000097:blood; D011863:Radioimmunoassay; D013739:Testosterone / Q000097:blood
D006062:Gonadotropins; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone