The Action of Nicotine in the Mammalian Brain
Acetylcholine (ACh) is one of the predominant neurotransmitters in the brain. The majority of cholinergic cells are found in the medial septal nucleus, the basal forebrain, the striatum, and the brainstem (Struble et al. 1986). The major projection areas include cortex, hippocampus, striatum, substantia nigra, and medial habenula (Butcher 1995; Woolf et al. 1984). ACh is involved in the regulation of cortical arousal (Semba 1991), attention (Murphy and Sillito 1991), and sleep-wake cycles (Hobson 1990). Thus, the actions of ACh are manifold. The actions of ACh are mediated by two different types of receptors: the ionotropic nicotinic type and the metabotropic muscarinic type. Each of these classes of ACh receptor (AChR) has multiple subtypes with unique structural and functional characteristics, and thus ACh released from a nerve terminal may contribute to a wide variety of brain functions by activating different intracellular pathways depending on the distribution of the receptor types.
KeywordsNicotinic Receptor Basal Forebrain Nicotinic Acetylcholine Receptor Cholinergic System Population Spike
Unable to display preview. Download preview PDF.
- Alkondon M, Pereira EFR, Albuquerque EX (1996b) Characterization of nicotinic acetylcholine receptors in CA1 neurons of rat hippocampal slices. Soc Neurosci Abstr 22:1267Google Scholar
- Butcher LL (1995) Cholinergic neurons and networks. The rat nervous system. Academic Press, New York, pp 1003–1015Google Scholar
- Chavez NL, Crona JH, Washburn MS, et al (1997) Pharmacological characterization of recombinant human neuronal nicotinic acetylcholine receptors (α2β2, α2β4, α3β2, α3β4, α4β2, α4β4 and α7 expressed in Xenopus oocytes. J Pharmacol Exp Ther 280:346–356Google Scholar
- Heinemann S, Boulter J, Connolly J, et al (1991) The nicotinic receptor genes. Clin Neuropharmacol 14:S45-S61Google Scholar
- Levin ED (1993) Nicotinic involvement in cognitive function: possible therapeutic applications. Med Chem Res 2:612–627Google Scholar
- Newhouse PA, Potter A, Lenox RH (1993) The effects of nicotinic agents on human cognition: possible therapeutic applications in Alzheimer’s and Parkinson’s diseases. Med Chem Res 2:628–642Google Scholar