Hormonal regulation of adrenal cortex vascularization

摘要: The development of a vascular network is a fundamental requirement for organ growth and differentiation during embryogenesis as well as during tissue repair or regeneration. The mass of adult tissues is essentially constant and results from a steady state between appoptosis of senescent cells and tightly controlled regenerative proliferation. There are however a number of physiological and pathological situations under which this equilibrium can be disrupted. A few examples are the oestrusdependent cycles of growth and vascular remodeling of the female endocrine organs (ovaries, uterus), the variations in fat tissue mass induced by modifications of the basal metabolism and the regeneration of the liver following partial hepatectomy. In each of these situations, the vascular network appears to regress or develop in parallel with the differentiated cells of these organs, suggesting that some tightly controlled paracrine regulatory loops exist between these two cell types. In addition to its well-established function of nutrient and gas exchange between tissues and blood, the endothelium thus appears to play multiple homeostatic roles. The implication of angiogenic factors, such as members of the VEGF family, in the control of tissue mass has been characterized in several organs. One of the first example was the demonstration by Franck-Lissbrant et al. and Haggström et al. that testosterone stimulates angiogenesis and vascular regrowth in the prostate of castrated rats (1, 2). During testosterone-induced regeneration of the prostate of castrated rats, the proliferation of endothelial cells appeared to increase 3-fold in the first day and then normalize by …