Mechanisms underlying reserpine-induced ptosis and blepharospasm: evidence that reserpine decreases central sympathetic outflow in rats

Reserpine-induced blepharospasm in rats is a central action mediated through the temporal and zygomatic branches of the facial nerve. Reserpine-induced ptosis, on the other hand, occurs as a consequence of reduced sympathetic outflow. Evidence is presented that this reduction in sympathetic outflow occurs as a consequence of peripheral depletion of norepinephrine from postganglionic sympathetic nerve endings as well as via a central or preganglionic reduction in sympathetic outflow. The degree of central as opposed to peripheral effect is apparently dependent on pretreatment time as well as on the dose of reserpine administered.