Nicotinic Ganglionic Blocker

Excerpt

Nicotinic ganglion receptors found in the autonomic ganglia are involved in both sympathetic and parasympathetic transmission. These receptors classify as neuronal nicotinic (Nn) cholinergic receptors, and they are on postganglionic efferent neurons. The activation of the Nn receptor is mediated by the release of acetylcholine from preganglionic efferent neurons. Interruption of acetylcholine-receptor binding at the level of the autonomic ganglia results in complete interruption of both sympathetic and parasympathetic signaling. Mecamylamine is one of the first nicotinic ganglion blockers widely used as a therapeutic agent, and it was originally introduced as an antihypertensive medication. Increased sympathetic activity results in vascular vasoconstriction, and subsequently elevated blood pressure, as a result of Alpha-1 receptor stimulation. Mecamylamine's ability to blockade sympathetic activity at the level of the autonomic ganglia explains its long-time usage as an antihypertensive agent.