Related Experiment Video
Updated: Aug 14, 2026

Spectral Confocal Imaging of Fluorescently tagged Nicotinic Receptors in Knock-in Mice with Chronic Nicotine Administration
Published on: February 10, 2012
Effect of nicotine on single cell activity in the noradrenergic nucleus locus coeruleus
Abstract:
The effect of nicotine and various cholinergic and anticholinergic drugs on brain noradrenaline (NA) containing neurons in the locus coeruleus (LC) of the rat was studied utilizing single cell recording techniques and microiontophoretic drug application. Nicotine (10--50 micrograms/kg i.v.) caused a dose-dependent, short-lasting increase in the firing rate of NA neurons in the LC. When microiontophoretically applied nicotine had no effect on LC neurons, which in contrast were activated by acetylcholine (ACh) and the muscarinic agonist, bethanechol. The stimulation of NA neurons in the LC by i.v. physostigmine was antagonized by scopolamine but not by methylscopolamine. Also microiontophoretically applied scopolamine specifically antagonized the NA-cell activation by ACh. Consequently, nicotine probably causes an indirect activation of NA neurons in the LC. These cells seem to be equipped with excitatory, cholinergic receptors of muscarinic but not nicotinic character. The LC activating effect of nicotine may be important for its arousal producing properties.
Related Concept Videos
Cholinergic Receptors: Nicotinic
There are two types of nicotinic receptors: neuromuscular (NM/NM/N1) and neuronal (NN/NN/N2). The two families differ based on their location and selectivity to...
Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
The direct-acting...
Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...
Adrenergic Neurons: Neurotransmission
Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
Adrenergic Receptors: β Subtype
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Parasympathetic Signaling
The effects of...

