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O livro utilizado foi: CARLSON, Bruce M. Human Embryology and Developmental Biology. 6th ed. Elsevier, 2019. Cap. 1: Getting Ready for Pregnancy. A imagem do slide foi retirada desta referência.

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"The meiotic arrest at the diplotene stage of the first meiotic division is the result of a complex set of interactions between the oocyte and its surrounding layer of follicular (granulosa) cells. The principal factor in maintaining meiotic arrest is a high concentration of cyclic adenosine monophosphate (cAMP) in the cytoplasm of the oocyte (Fig. 1.11). This is accomplished by both the intrinsic production of cAMP by the oocyte and the production of cAMP by the follicular cells and its transport into the oocyte through gap junctions connecting the follicular cells to the oocyte. In addition, the follicular cells produce and transport into the oocyte cyclic guanosine monophosphate (cGMP), which inactivates phosphodiesterase 3A (PDE3A), an enzyme that converts cAMP to 5′AMP. The high cAMP within the oocyte inactivates maturation-promoting factor (MPF), which at a later time functions to lead the oocyte out of meiotic arrest and to complete the first meiotic division."...

... "The resumption of meiosis in response to the LH surge is initiated by the cumulus (granulosa) cells because the oocyte itself does not possess LH receptors. Responding to LH, the cumulus cells shut down their gap junctions (see Fig. 1.11B). This reduces the transfer of both cAMP and cGMP from the cumulus cells into the oocyte. The resulting reduction of cGMP in the oocyte allows the activation of PDE3A. The activated PDE3A then breaks down the intraoocytic cAMP into 5′AMP. The decline in the concentration of cAMP sets off a signaling pathway leading to the activation of MPF and the subsequent resumption of meiosis."

Bons estudos,

Profa. Luciana