Excitatory effects on renal sympathetic nerve activity induced by stimulation at two distinctive sites in the fastigial nucleus of rabbits.

Tetanic stimulation of the fastigial nucleus in anesthetized rabbits induced a rise in blood pressure and concomitantly increased activity of the ipsilateral renal sympathetic nerve. Two distinctive, effective sites were thus found, one in the rostro-ventro-medial portion and the other in the caudo-medial portion of the fastigial nucleus. The results suggest the existence of two separate groups of fastigial neurons playing different roles in cardiovascular function.