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Updated: Aug 19, 2026

A Computerized Test Battery to Study Pharmacodynamic Effects on the Central Nervous System of Cholinergic Drugs in Early Phase Drug Development
Published on: February 11, 2019
Choline administration: lack of effect on plasma catecholamines in rats
Abstract:
Choline chloride (35 or 70 mg/kg, IP) or saline was administered daily for 3 consecutive days to adult male Sprague-Dawley rats. Before and 30, 60 and 120 minutes after the third injection of choline chloride or saline, blood samples were collected from a chronic tail artery catheter and later analyzed for levels of norepinephrine (NE) and epinephrine (EPI). Plasma levels of both catecholamines did not differ between choline- and saline-injected rats at either of the four sampling points. When insulin (10 IU/kg, SC) was administered to stimulate the sympathetic-adrenal medullary system reflexly, plasma levels of NE and EPI increased significantly above basal values but were similar for choline- and saline-injected rats. These findings do not support a role for choline availability in the regulation of catecholamine secretion from the adrenal medulla.
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