Excitatory control of hypothalamic ventromedial nucleus by basolateral amygdala in rats

Effects of single and repetitive stimulation of the basolateral amygdaloid nucleus (AL) on the rat hypothalamic ventromedial nucleus (VMH) activity were investigated. Extracellular single unit discharges and evoked potentials were recorded in the VMH and stria terminalis using microelectrodes. Three effects of AL stimulation on the VMH were observed: exitation, inhibition, and disinhibition. Disinhibition may, in fact, be inhibition of inhibitory interneurons within the VMH. Finally, a tentative concept of the neural network within the VMH is discussed.