| Popis: |
The overall aim of our research is to elucidate control of the production and mechanisms of action of inhibin (INH), activin (ACT), and follistatin (FS) in the pituitary and ovary. The broad hypothesis being tested is that, apart from the endocrine actions of INH on the pituitary, these substances exert autocrine or paracrine actions on the gonadotrophs in the pituitary and the follicular cells of the ovary to regulate follicle-stimulating homone (FSH) secretion and folliculogenesis, respectively. To test this hypothesis, it is necessary to demonstrate (a) that the cells of the pituitary and ovary are capable of secreting INH, ACT, and FS in a timely manner, and (b) that these substances can modify the functions of the target cells in a manner consistent with their roles in regulating pituitary and ovarian function. We also need to know the forms in which INH, ACT, and FS are secreted and measure the relative biological activities of these forms. To this end, we have concentrated on the following specific questions: a. What are the relative biological activities of the high molecular weight (MW) forms of INH and ACT identified in biological fluids? b. Can expression of the FS and INH-α and -β mRNA or protein be detected in pituitary and ovarian cells at times consistent with their proposed roles? c. Is there a role for ACT in the acquisition of responsiveness of follicular granulosa cells to FSH during the early stages of folliculogenesis? |
