The corpus luteum of goldfish (Carassius auratus L.) and its functions.

This investigation of the role of pre- and post-ovulatory corpus luteum provided a better understanding of the various functions of follicular tissues in goldfish ovaries. When yolky oocytes become atretic, either naturally or under adverse conditions, the granulosa cells hypertrophy and serve a phagocytic function. This is evident in the α and β stages of the preovulatory corpus luteum. In addition to the removal of atretic oocytes, the follicular cells are involved in steroidogenesis, as demonstrated by the detection of hydroxysteroid dehydrogenases in the granulosa of normal oocytes and the corpus luteum, both pre- and post-ovulatory. In the preovulatory corpus luteum the steroidogenic function was evident only after the complete removal of the atretic oocyte. Hence, steroidogenesis was observed only in the γ stage preovulatory corpus luteum. In the postovulatory follicles, steroidogenesis was evident immediately after ovulation. It is postulated that the steroid hormones synthesized by the pre- and po...