Figure 9.

Cartoon summary of neuroendocrine changes in the LET PCOS-like model. Letrozole-treated females exhibit greater numbers of detectable Kiss1/Tac2/Pdyn cells and higher Kiss1, Tac2, and Pdyn mRNA levels per cell in the ARC nucleus (represented by larger cell size and darker green color), as well as increased ARC Kiss1 neuron activation (represented by the yellow star bursts), relative to normal control females. Letrozole-treated females correspondingly demonstrate faster, higher amplitude LH pulse patterns compared to normal females, providing a greater gonadotropin drive to the ovary. Whether or not similar brain alterations are present in some PCOS women is a possibility but is currently unknown.