Histologic evaluation of the sympathectomy induced by guanethidine sulfate in neonatal rats.

Guanethidine sulfate was administered to rats from birth to 14 days of age. Cell counts were carried out in the superior cervical sympathetic ganglion at 30, 45, and 90 days of age. Massive permanent destruction of sympathetic ganglionic cells was demonstrated during the experimental period. Evidence for a natural loss of neurons during the morphogenesis of the superior cervical sympathetic ganglion is presented.