Folliculogénèse

The maturation of the Follicule ovarien during the menstrual Cycle is stimulated by the Gonadotrophine S secreted by the Antéhypophyse: the FSH (folliculo-stimulative Hormone) and the Hormone lutéinisante (LH).

Follicular development

paramount Follicule : The Ovocyte is surrounded by a single layer of cells (somatic) flattened, the follicular cells , of epithelial origin , to form the paramount follicules . A stock of reserve of paramount follicules is thus made up. Continuously, certain follicules escape and start a phase of growth.
primary education Follicule : The follicule grows bigger. From puberty, 15 to 20 follicules develop, but only one or two arrives at maturation. The follicular cells become cubic and constitute a continuous base around the ovocyte.
secondary Follicule : The primary education follicule continues to develop. A glycoproteic layer is formed between the follicular Ovocyte and cells (pellucid Zone). The pellucid zone is secreted by the ovocyte, it intervenes in the specific recognition of the spermatozoon. The Stroma of the conjunctive Tissu starts to form a autoure layer of the follicule (thèque follicular). The follicule continues to increase volume and the follicular cells proliferate to form several layers of cells forming the Granulosa.
tertiary Follicule : The granulosa proliferates much. Formation of a follicular cavity (the antrum . The antrum fills of a liquid rich in hormones (estrogen) and AMPcyclique. The thèque one undergoes a morphological and functional differentiation. One sees at this stage a thèque very vascularized intern and thèque external of fibro-muscular nature (its contraction allows the ejection of the ovule).
Follicule of Graaf : The growth of the ovocyte ceases. Ovocyte I becomes ovocyte II pennies the effect of the discharge ovulante of LH, and remains thus blocked in Métaphase of the second division in waiting of possible a Fécondation.

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