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What is Which of the following cells are the target site for FSH action? and explain in detail?
During the follicular phase, estrogen levels rise in parallel to growth of a dominant follicle and the increase in its number of granulosa cells. These cells are the exclusive site of FSH receptor expression. The increase in circulating FSH during the late luteal phase of the previous cycle stimulates an increase in FSH receptors. The requirement for thecal cells, which respond to luteinizing hormone (LH), and granulosa cells, which respond to FSH, represents the two-gonadotropin, two-cell hypothesis for estrogen biosynthesis. Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 3. Implantation, Embryogenesis, and Placental Development. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.