RT Journal Article
SR Electronic
T1 TRANS-SYNAPTIC INDUCTION OF CHOLINE ACETYLTRANSFERASE IN THE PREGANGLIONIC NEURON OF THE PERIPHERAL SYMPATHETIC NERVOUS SYSTEM
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 439
OP 446
VO 188
IS 2
A1 Oesch, Franz
YR 1974
UL http://jpet.aspetjournals.org/content/188/2/439.abstract
AB After treatment of rats with reserpine, the in vitro activity of choline acetyltransferase increased in the stellate and superior cervical ganglia and in the adrenal gland. This enzyme is confined to preganglionic nerve terminals, as demonstrated for the latter two organs. The increase was dose-dependent and persisted for three days after a single dose of the drug. Choline acetyltransferase activities in preparations from reserpinetreated and control animals were additive and the Km for substrate and for cofactor were not changed after reserpine treatment. These observations indicate that the increase in enzyme activity is not due to the disappearance of an inhibitor, to the formation of an activator or to an alteration of the active site but rather to an increase in the number of active sites. This increase in enzyme activity was prevented by concomitant administration of cycloheximide, indicating that the rise is dependent on protein synthesis. Transection of the spinal cord at the level of the 5th thoracic vertebra completely prevented the rise in activity of choline acetyltransferase in the adrenal glands. It is concluded that a prolonged increase in the activity of the fibers supplying the preganglionic cholinergic neurons of the peripheral sympathetic nervous system leads to an induction of choline acetyltransferase in the latter. © 1974 by The Williams & Wilkins Co.