Availability of metabolic fuels controls estrous cyclicity of Syrian hamsters.

Food deprivation and weight loss inhibit ovulation and estrous behavior in Syrian hamsters. In the present experiments, lean hamsters were more susceptible to starvation-induced anestrus than fat hamsters. However, anestrus was not caused by changes in any dimension of body size per se, but instead by the availability of metabolic fuels. Simultaneous pharmacological blockade of both fatty acid oxidation and glycolysis inhibited reproduction, but, as long as one of these metabolic pathways could be used, estrous cycles continued. Thus, reproduction in female Syrian hamsters is sensitive to the general availability of oxidizable metabolic fuels.