It is well established that ovulation in mammals occurs as a result of an endogenous pre-ovulatory LH surge. Gonadotrophins, such as hCG and PMSG, which have LH activity, also induce ovulation. The ovulatory process comprises alterations in the steroidogenesis, resumption of oocyte meiosis (discussed in Chaps. IV and VI), morphological and biochemical transformation of the cumulus oophorus (described in Chap. IV), luteinization of the granulosa cells (discussed in Chap. VI), and finally follicular rupture and release of the mature ovum, to be discussed in this chapter. The results of recent experimental studies have indicated that the processes of follicular rupture, ovum maturation and ovarian steroid production can proceed independently of one another (Bongiovanni et al. 1983, Testart 1983). Rondell (1974) has discussed the role of steroid and gonadotropic hormones in the process of ovulation at the cellular level (see also Schwartz 1974). During ovulation, the granulosa, theca interna and surface epithelium undergo major biophysical and biochemical changes (Lipner 1973, Espey 1974, 1978a, b, Guraya 1974a, 1979c), which will be discussed here in order to assess the increase in our kowledge about the cellular, subcellular and molecular aspects of the mechanism of ovulation.
KeywordsGranulosa Cell Follicular Fluid Prostaglandin Synthesis Tunica Albuginea Ovulatory Process
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