Abstract
The objective of the present study was to investigate the influence of prostaglandin F2α (PGF 2α) and nitric oxide (NO) on production of steroids and PGs by culturing bovine luteal cells obtained from ovaries on days 8-12 of the estrous cycle with a nitric oxide (NO) donor (Spermine NONOate), and a NO synthase inhibitor (NG-nitro-L-arginine methyl ester dihydrochloride: L-NAME). When the cells were exposed for 24 h to PGF2α (10-7-10-5 M), production of progesterone (P4) increased significantly at all doses used (P<0.05). Moreover, PGF2α stimulated PGF2α production (P<0.01), depressed testosterone (T) production (P<0.05), but did not affect synthesis of prostaglandin E2 (PGE2). Spermine NONOate decreased P4 production to 66%, 47% and 34% of the control concentration after treatment with 10-5 M, 10-4 M and 10-3 M, respectively, but did not affect T production, and increased PGF2α synthesis (P<0.05) and PGE2 (P<0.01) at all doses used. L-NAME increased production of P4 (P<0.01) but did not affect (P>0.05) secretion of T, PGF2α and PGE2. Estradiol-17β (E2) was detectable on the level of sensitivity of assay and was not significantly altered by any treatments. The overall results suggest that PGF2α and NO produced locally in bovine CL play roles in the regulation of the secretory function of the bovine CL as auto/paracrine factors.
