The raphe magnus/pallidus regulates sweat secretion and skin vasodilation of the cat forepaw pad: A preliminary electrical stimulation study

In the human palm/sole, mental or physical stimuli induce an increase in sweat secretion and a decrease in skin blood flow (SkBF). However, the central pathways of these responses remain unclear. We measured sweat secretion and SkBF in the cat footpad by electrically stimulating the raphe. Stimulation of the rostral raphe magnus/pallidus elicited a reduction in SkBF without affecting sweat secretion. Stimulation of the mid to caudal raphe magnus/pallidus elicited an increase in both sweat secretion and SkBF. The raphe magnus/pallidus may play a crucial role in skin vasomotor and sudomotor responses in the cat footpad.