The atypical 5-HT2 receptor mediating tachycardia in pithed rats: pharmacological correlation with the 5-HT2A receptor subtype

British Journal of Pharmacology
David CenturiónCarlos M Villalón

Abstract

1. In pithed rats, 5-HT mediates tachycardia both directly (by 5-HT(2) receptors) and indirectly (by a tyramine-like effect). The receptor mediating tachycardia directly has been classified as an 'atypical' 5-HT(2) receptor since it was 'weakly' blocked by ketanserin. Moreover, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a 5-HT(2) agonist, failed to mimic 5-HT-induced tachycardia. Since 5-HT(2) receptors consist of 5-HT(2A), 5-HT(2B) and 5-HT(2C) subtypes, this study investigated if these subtypes mediate the above response. 2. In pithed rats, intraperitoneally (i.p.) pre-treated with reserpine (5 mg kg(-1)), intravenous (i.v.) administration of 5-HT, 5-methoxytryptamine (5-MeO-T), 1-(3-chlorophenyl) piperazine (mCPP) and 5-carboxamidotryptamine (5-CT) (10, 30, 100 and 300 microg kg(-1) each), produced dose-dependent tachycardic responses. Interestingly, DOI (10 - 1000 microg kg(-1), i.v.) induced only slight, dose-unrelated, tachycardic responses, whilst the 5-HT(2C) agonist, Ro 60-0175 (10 - 1000 microg kg(-1), i.v.), produced a slight tachycardia only at 300 and 1000 microg kg(-1). In contrast, sumatriptan and 1-(m-trifluoromethylphenyl)- piperazine (TFMPP) were inactive. The rank order of potency was: 5-HT > or =5-...Continue Reading

References

Jan 1, 1990·Journal of Cardiovascular Pharmacology·P R Saxena, C M Villalón
Jun 1, 1991·Trends in Pharmacological Sciences·P R Saxena, C M Villalón
Sep 22, 1989·European Journal of Pharmacology·H DabiréH Schmitt
Jan 1, 1988·Naunyn-Schmiedeberg's Archives of Pharmacology·J R Docherty
Apr 1, 1997·Neuropharmacology·D W BonhausR M Eglen
Jul 1, 1997·British Journal of Pharmacology·C M VillalónP R Saxena
Feb 12, 1998·Naunyn-Schmiedeberg's Archives of Pharmacology·D B WainscottD L Nelson
Mar 1, 1964·Journal of Applied Physiology·L I KLEINMAN, E P RADFORD
Apr 1, 1947·Proceedings of the Society for Experimental Biology and Medicine·R E SHIPLEY, J H TILDEN

❮ Previous
Next ❯

Citations

Aug 19, 2007·Naunyn-Schmiedeberg's Archives of Pharmacology·Carlos M Villalón, David Centurión
Feb 8, 2014·PloS One·Hitoshi WatanabeHisashi Aso
Dec 17, 2003·Proceedings of the National Academy of Sciences of the United States of America·Miro Smriga, Kunio Torii
Mar 21, 2006·European Journal of Pharmacology·David CenturiónCarlos M Villalón
Oct 13, 2004·European Journal of Pharmacology·David CenturiónCarlos M Villalón
Jan 28, 2017·Journal of Experimental Zoology. Part A, Ecological Genetics and Physiology·Vernon Beasley, Harold Dowse
Sep 2, 2004·British Journal of Pharmacology·Pieter JanssenRomain A Lefebvre
Apr 9, 2020·Canadian Journal of Physiology and Pharmacology·Oscar Alcántara-VázquezDavid Centurión
Jul 24, 2021·Journal of Pharmacological Sciences·José Ángel García-PedrazaMónica García-Domingo

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antihypertensive Agents: Mechanisms of Action

Antihypertensive drugs are used to treat hypertension (high blood pressure) which aims to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Discover the latest research on antihypertensive drugs and their mechanism of action here.