Autocrine/paracrine regulation of normal human corpus luteum development.

The human corpus luteum (CL) is a transient endocrine gland regulated primarily by the age-dependent action of LH/hCG, which initiates a series of cell-specific processes necessary for the structure and also function of the gland. An extensive local regulation of the luteal function also exists, based on the heterogeneity of the cellular composition of the CL. It is most likely that interactions occur among the different subpopulations of steroidogenic (large and small luteal cells) and nonsteroidogenic cells (leukocytes, endothelial cells, and fibroblasts). Therefore, local produced substances, including steroids, growth factors, reactive oxygen species, and, recently, nitric oxide, may modulate luteal life span. The knowledge of the basic events involved in the control of human luteal function may lead to a better understanding of the physiopathology of the human menstrual cycle.