Pharmacological Analysis of Acetylcholinesterase‐rich Ganglion Cells in the Lumbo‐sacral Sympathetic System of the Cat

Recent studies have indicated that AcChE‐rich or type I‐cells in the stellate ganglion of the cat give rise to cholinergic sweat secretory fibres rather than vasodilator fibres. The purpose of the present investigation was to prove this hypothesis. Type I‐neurons were found in significant amounts exclusively in those lumbo‐sacral ganglia that innervate the eccrine sweat glands of the hind paw. The 7th lumbar ganglion always contained the highest proportion (10.8 %), whereas the other ganglia possessed lower amounts, viz. S1, 7.7 %; L6, 3.5 %; and S2 1.9 %. Occasional type I‐cells were demonstrated in L5 but practically none in other Jumbo‐sacral ganglia. The sweat secretory responses on the hind paw were always proportional to the number of type I‐cells in the stimulated ganglia. The vasodilator responses evoked from ganglia crcmded with type I‐cells and from those lacking such cells were on the other hand approximately equivalent. The results form the basis for the conclusion that the type I‐cells in the stellate ganglion and in the ganglia between L6 and S2 are identical with cholinergic sweat secretory neurons.