Nitric oxide induces apoptosis in the human corpus luteum in vitro

Citation
M. Vega et al., Nitric oxide induces apoptosis in the human corpus luteum in vitro, MOL HUM REP, 6(8), 2000, pp. 681-687
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
MOLECULAR HUMAN REPRODUCTION
ISSN journal
1360-9947 → ACNP
Volume
6
Issue
8
Year of publication
2000
Pages
681 - 687
Database
ISI
SICI code
1360-9947(200008)6:8<681:NOIAIT>2.0.ZU;2-8
Abstract
The present study aimed to investigate the role of nitric oxide (NO) in reg ression of the human corpus luteum. We therefore examined the effect of bot h NO and human chorionic gonadotrophin (HCG) on luteal cell apoptosis, and Bcl-2 production. The effect of NO on oestrogen production during corpus lu teum regression was also studied. Slices from corpus luteum collected throu ghout the luteal phase were incubated for 4 h with the nitric oxide synthas e (NOS) substrate, L-arginine (L-Arg, 1 mmol/l), the NOS inhibitor N-monome thyl-L-arginine (L-NMMA) (1 mmol/l), or with HCG (10 IU/ml), Oestradiol con centrations were determined by radioimmunoassay; Bcl-2 concentrations were measured by enzyme-linked immunosorbent assay; apoptosis was detected in-si tu by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labellin g; and inducible nitric oxide synthase (iNOS) was assessed by immunohistoch emistry, Consistent with our previous findings, L-Arg elicited an inhibitor y action on the production of oestradiol (P < 0.05), The number of apoptoti c cells increased (P < 0.05) from early to late corpus luteum, as did the n umber of cells positive for the expression of iNOS. The percentage of apopt otic cells in mid and late luteal phase was increased by L-Arg (56% and 310 % respectively; P < 0.05), and decreased by L-NMMA and HCG. Although no cha nges were observed in Bcl-2 concentration during the corpus luteum life spa n, L-Arg inhibited, and HCG augmented, Bcl-2 production (P L 0.05) from mid and late corpus luteum cells in vitro. In summary, these results suggest t hat the opposite actions of L-Arg and HCG on human corpus luteum viability may, in part, be mediated by changes in the level of the anti-apoptotic act ivities caused by oestradiol and Bcl-2 protein.