ABSTRACT
Adaptive changes of temperature regulation to different environmental temperatures are regarded to involve central and/or peripheral thermosensors. Adaptive changes to different environmental temperatures have been reported on noradrenergic and serotonergic pathways, ascending from lower brainstem nuclei to the hypothalamus. One feasible way to test possible adaptive changes at the neuronal level is to study the effect of a potent neuromodulator on neurons from animals adapted to cold or warm environments. A long lasting and consistent change of the activity of rat hypothalamic warm sensitive and temperature-insensitive neurons was observed after the application of the peptidergic synaptic modulators bombesin and substance P in vitro. It has been suggested that a reaction of the hypothalamic circuitry responsible for the regulation of body temperature is more dependent on the individual temperature sensitivity of a neuron than on its change in a tonic activity.
