Fig. 1.
Impact of VIP-deficiency on estrous cycles. A. VIP-deficiency results in disrupted estrous cycles (middle and bottom) compared to the 4–5 day estrous cycles exhibited by WT females (top). P: proestrus, majority nucleated epithelial cells. E: estrus, cornified cells. D/M: diestrus or metestrus, presence of leukocytic cells. B. The average length of an estrous-to-estrous cycles in VIP-deficient mice is longer than in WT females (* P < 0.05). C. VIP-deficiency reduces the number of proestrus to estrus transitions. D. The number of consecutive days in di- and met-estrus increase with the loss of VIP (* P < 0.05).