Cytochromes P-450scc, P-45017α, Adrenodoxin, and Reduced Nicotinamide Adenine Dinucleotide Phosphate-Cytochrome P-450 Reductase in Bovine Follicles and Corpora Lutea. Changes in Specific Contents during the Ovarian Cycle*

摘要: To investigate the basis for pattern of ovarian steroid production during bovine estrous cycle, tissue concentrations major steroidogenic enzymes, 17 alpha-hydroxylase cytochrome P-450 and cholesterol side-chain cleavage (cytochrome P-450scc), their respective electron donors, NADPH-cytochrome reductase adrenodoxin, were estimated compared with those nonsteroidogenic c oxidase F1-ATPase. The levels these enzymes in medium sized (9-11 mm) large (14-18 follicles after removal follicular fluid by centrifugation, corpora lutea from early, early-mid late-mid, late stages luteal phase (n = 5 per group). specific contents all donors determined immunoblot analysis, except oxidase, which was quantified determination activity. (per microgram homogenate protein) total follicle or corpus luteum) increased 0.5- 5-fold respectively to follicles, but then decreased undetectable early phase, remained throughout phase. In contrast, content similar between lutea. P-450scc, adrenodoxin However, P-450scc (490 +/- 46 vs. 5709 982 cpm/micrograms (44 15 705 229 increased, 12- 15-fold, (P less than 0.05). activity (29.1 10.1 108.6 20.7 nmol/mg protein X min) F1-ATPase only 3- 4-fold reflective an increase numbers mitochondria. elevated until when they declined markedly. It is concluded that induction synthesis ovulation does not merely reflect biogenesis mitochondria luteinization. Moreover changes types steroids produced compartments cycle are a reflection enzymes.