REVIEW In general, alpha1-adrenergic receptors mediate contraction and hypertrophic growth of smooth muscle cells. alpha1-receptors are 7-transmembrane domain receptors coupled to G proteins, Gq/11. Three alpha1-receptor subtypes, which share approximately 75% homology in their transmembrane domains, have been identified: alpha1A (chromosome 8), alpha1B (chromosome 5), and alpha1D (chromosome 20). Phenylephrine appears to act similarly on all three receptor subtypes. All three receptor subtypes appear to be involved in maintaining vascular tone. The alpha1A-receptor maintains basal vascular tone while the alpha1B-receptor mediates the vasocontrictory effects of exogenous alpha1-agonists. Activation of the alpha1-receptor activates Gq-proteins, which results in intracellular stimulation of phospholipases C, A2, and D. This results in mobilization of Ca2+ from intracellular stores, activation of mitogen-activated kinase and PI3 kinase pathways and subsequent vasoconstriction. Phenylephrine produces its local and systemic actions by acting on alpha1-adrenergic receptors peripheral vascular smooth muscle. Stimulation of the alpha1-adrenergic receptors results in contraction arteriolar smooth muscle in the periphery. Phenylephrine decreases nasal congestion by acting on alpha1-adrenergic receptors in the arterioles of the nasal mucosa to produce constriction; this leads to decreased edema and increased drainage of the sinus cavities. It also increases blood pressure as an aid in the diagnosis of heart murmurs.
REFERENCES
[1]
Heldeles, L. and Hatton, R. (2006). Oral phenylephrine: An ineffective replacement for pseudoephedrine?. Journal of Allergy and Clinical Immunology 118 (1): 279-280. doi:10.1016/j.jaci.2006.03.002. PMID 16815167.
[2]
Eccles, R. (2007). Substitution of phenylephrine for pseudoephedrine as a nasal decongeststant. An illogical way to control methamphetamine abuse. British Journal of Clinical Pharmacology 63 (1): 10-14. doi:10.1111/j.1365-2125.2006.02833.x. PMC 2000711. PMID 17116124.
[3]
Kollar, C.; Schneider, H.; Waksman, J.; Krusinska, E. (2007). Meta-analysis of the efficacy of a single dose of phenylephrine 10 mg compared with placebo in adults with acute nasal congestion due to the common cold. Clinical Therapeutics 29 (6): 1057-1070. doi:10.1016/j.clinthera.2007.05.021. PMID 17692721.
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