Special Physics Seminar

Babies or no babies, an intimate story between mathematical modeling and the physiology of GnRH neurons

Anmar Khadra

Department of Physiology
McGill University

The onset of puberty and fertility in mammals are controlled by the release of a specific hormone called Gonadotropin-Releasing Hormone (GnRH). This hormone is secreted by neurons (called GnRH neurons) located in the hypothalamus above the brain stem. These neurons secrete the hormone periodically (once every hour in humans) with a specific pattern characterized by sharp pulses separated by inactive periods. There is a strong evidence suggesting that GnRH neurons are intrinsically capable of secreting the hormone without any feedback from other systems. The underlying mechanism regulating the hormone release, however, remains obscure. We have developed a mathematical model based on a recently proposed mechanism to describe the dynamics (and physiology) of not only one isolated GnRH neuron, but also a network of these neurons connected together by a shared pool of this hormone. The model demonstrates the robustness of this biological system and how synchrony between these neurons is attained under various conditions. In this talk, I will present this model and analyze various aspects of it.