Abstract
During 3hr of incubation, the production of progesterone in the follicle wall from the largest preovulatory follicle (F1) of the Japanese quail was stimulated by ovine LH or dibutyryl cyclic AMP. The follicle walls from the second largest and the third largest follicles (F2 and F3) did not produce appreciable amounts of progesterone, while the granulosa cells isolated from these follicles produced significant amounts of progesterone. By incubating progesterone with the cell-free homogenates of the theca layer in the presence of NADPH, it was clarified that the metabolic rates of progesterone in the theca layer of F2 and F3 were higher than that of F1. These results suggested that in the quail follicles, progesterone is produced in the granulosa layer but the theca layers of the small follicles metabolize progesterone, so that only F1 secretes progesterone.
