Adrenergic Activity in Hypothalamus and Ovulation 1

Summary

Adrenergic activity of the hypothalamus prior to and subsequent to ovulation was evaluated in rats. Turnover of hypothalamic norepinephrine was measured by following the decline of endogenous NE levels after synthesis blockade with α-methyl-p-tyrosine methylester. Proestrous rats showed both a greater concentration and depletion of NE than estrous rats. Coincidentally, in proestrous rats an increased synthesis of hypothalamic NE as measured from the conversion of ³H-tyrosine to ³H-NE was observed. These results suggest that an increased NE activity takes place in the rat hypothalamus before ovulation.