Abstract: In rabbits under local anesthesia and immobilization extrasystales and elevation of arteral blood pressure could be provoked by stimulation of the Lateral Hypothalamic Area (LHA) and Ventromedial Hypothalamic Nucleus (VMH) with 15～70μA, 70Hz and 1ms duration square wave current. They have relatively differential. Brady-arrythmias, bradycardias, sinus cadiac arrest and block, could be provoked and its produce rade was higher during stimulation of LHA; on the other hand, tacky-arrythmias, frequent Hypothalamic stimulation-induced Ventricular Extrasystale (HVE) and tackycardias could be provoked and its produce rate Was higher during stimulation of VMH. Stimlus-eveked brady-arrythmia of LHA or VMH could be deleted or damped by injection Atropine of bilateral vagotomy, but stimulus-evoked tacky-arrhythmai of VMH could be deleted of damped. Stimulus-evoked tacky-arrythmia of VMH of LHA could be abated or damped by injection of Phentolamin and/or Propranolol, but stimulus-evoked brady-arrythmia of LHA could even more be enhanced of facilitied.

Key words: Lateral Hypothalamic Area (LHA), Ventromedial Hypothalamic Neucleus (VMH), arrhythams, pressor response