Amygdalofugal modulation of the vago-vagal gastric motor reflex in rat.

In experiments on urethane anaesthetized rats the influence of electrical stimulation of the central nucleus of the amygdala (CNA) on gastric motility and activity of gastric-related neurons of the dorsal vagal complex was studied. Stimulation of the CNA effected spontaneous gastric motility and caused both excitatory and inhibitory changes of vagal-induced gastric relaxation. The most significant effects, mainly inhibitory, were observed under stimulation of the medial CNA. This amygdaloid area was found to influence activity of gastric-related neurons of the dorsal vagal complex. Excitatory and inhibitory changes of their vagal-induced responses under the amygdala stimulation manifested as general modulation of all phases of the reaction or selective modulation of some of them. These mechanisms may lie at the base of amygdalofugal modulation of gastric reflex activity.