Decreased cued fear discrimination learning in female rats as a function of estrous phase.

Discrimination did not differ substantially across the nonproestrus phases of the estrous cycle, with animals showing a significant difference (or trend toward significance) between the CS+ and CS− in the estrus ( P = 0.01), metestrus ( P = 0.036), and diestrus ( P = 0.074) phases ( Fig. 3 B).

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