Cytochromes @entity21767 , P-450(17)alpha, adrenodoxin, and reduced nicotinamide adenine dinucleotide phosphate- XXXX in @entity291 follicles and corpora lutea. Changes in specific contents during the ovarian cycle.

@entity21767 @entity1110 @entity134 @entity70880 @entity230 @entity21304 @entity291 @entity165
To investigate the basis for the pattern of ovarian @entity134 production during the @entity291 estrous cycle, the tissue concentrations of major steroidogenic enzymes, 17 alpha-hydroxylase cytochrome P-450 and @entity165 side-chain cleavage cytochrome P-450 ( @entity21767 ), and their respective electron donors, @entity1110 - @entity70880 and adrenodoxin, were estimated and compared with those of the nonsteroidogenic enzymes, @entity21304 and F1-ATPase. The levels of these enzymes were estimated in medium sized (9-11 mm) and large (14-18 mm) follicles after removal of follicular fluid by centrifugation, and corpora lutea from the early, early-mid late-mid, and late stages of the luteal phase (n = 5 per group). The specific contents of all enzymes and electron donors were determined by immunoblot analysis, except for @entity21304 , which was quantified by determination of specific activity. The specific (per microgram of tissue homogenate protein) and total (per follicle or corpus luteum) tissue contents of 17 alpha-hydroxylase cytochrome P-450 increased 0.5- and 5-fold respectively from medium sized to large follicles, but then decreased to undetectable levels in corpora lutea in the early luteal phase, and remained undetectable throughout the luteal phase. In contrast, the specific content of @entity1110 - @entity70880 was similar between follicles and corpora lutea. The specific contents of @entity21767 , adrenodoxin and @entity21304 in follicles were similar to those of corpora lutea of the early luteal phase. However, by the early-mid luteal phase the specific contents of luteal cytochrome @entity21767 (490 +/- 46 vs. 5709 +/- 982 cpm/micrograms protein) and adrenodoxin (44 +/- 15 vs. 705 +/- 229 cpm/micrograms protein) were increased, by 12- and 15-fold, respectively (P less than 0.05). In contrast, @entity21304 activity (29.1 +/- 10.1 vs. 108.6 +/- 20.7 nmol/mg tissue protein X min) and the specific content of F1-ATPase increased only 3- to 4-fold reflective of an increase in numbers of mitochondria. The levels of these enzymes remained elevated until the late luteal phase when they declined markedly. It is concluded that the induction of synthesis of @entity21767 and adrenodoxin after ovulation is specific and does not merely reflect biogenesis of mitochondria during luteinization. Moreover the changes in the types of @entity230 produced by the ovarian compartments throughout the estrous cycle are a reflection of changes in the tissue content of steroidogenic enzymes.
