Cholinesterase activity in innervated and denervated sympathetic ganglion cells of the cat.

Abstract

AbstractTotal cholinesterase [ChE, acetylcholine (AcCh) as substrate] and acetylcholinesterase [AcChE, acetyl‐β‐methylcholine (MeCh) as substrate] were determined with the Cartesian diver in single sympathetic cell bodies isolated from the normal and preganglionically denervated 7th lumbar ganglion of the cat. Thirty normal cell bodies showed a wide variation in total ChE acitivity from 3 times 10‐‐4 to 160 times 10‐‐4 μl CO2/hour. Cell bodies with low activity represented the majority of the population, while cell bodies with very high activity were rare. AcChE‐activity in 10 normal cell bodies varied between 3.8 and 54.4 times 10‐‐4 μl CO2/hr. After denervation there was a significant decrease in average enzyme activity as measured with both substrates. This is probably explained by the loss of presynaptic AcChE‐rich terminals which stick to the normal cell bodies. With AcCh the enzyme activity varied between 2.7 and 28.5 times10‐‐4 μl CO2/hour (n = 16) and with MeCh between 2.9 and 31.1 times 10‐‐4 μl CO2/hour (n = 10). Thirty‐five per cent of the denervated cells (9/26) lacked measurable activity. The ratio of AcCh/MeCh hydrolysis decreased after denervation 1.7 to 1.0. These findings support the previous concept of two functionally different cell populations in sympathetic ganglia.