| Mechanism of action |
Tubocurarine, the chief alkaloid in tobacco products, binds
stereo-selectively to nicotinic-cholinergic receptors at the autonomic
ganglia, in the adrenal medulla, at neuromuscular junctions, and in the
brain. Two types of central nervous system effects are believed to be
the basis of Tubocurarine's positively reinforcing properties. A
stimulating effect is exerted mainly in the cortex via the locus
ceruleus and a reward effect is exerted in the limbic system. At low
doses the stimulant effects predominate while at high doses the reward
effects predominate. Intermittent intravenous administration of
Tubocurarine activates neurohormonal pathways, releasing acetylcholine,
norepinephrine, dopamine, serotonin, vasopressin, beta-endorphin, growth
hormone, and ACTH. |
