Blocking properties of terguride at the 5-ht2 receptor subtypes mediating cardiovascular responses in the rat

Oscar Alcántara-Vázquez, Ma Trinidad Villamil-Hernández, Araceli Sánchez-López, Heinz H. Pertz, Carlos M. Villalón, David Centurión

Research output: Contribution to journalArticlepeer-review

Abstract

In vitro studies have suggested that terguride blocks the contractile and relaxant responses produced by 5-hydroxytryptamine (5-HT) via 5-HT2A/2B receptors. This study has now investigated terguride’s blocking properties on central/peripheral 5-HT2 receptors in anaesthetized or pithed rats. Male Wistar anaesthetized/pithed rats were cannulated for recording blood pressure and heart rate and for i.v. administration of several compounds. In both groups of rats, i.v. bolus injections of 5-HT or (±)-DOI (a 5-HT2 receptor agonist; 1–1000 _g/kg) produced dose-dependent increases in diastolic blood pressure and heart rate. These responses were dose-dependently antagonized by terguride (10–3000_g/kg). In anaesthetized rats, i.v. bolus injections of BW723C86 (a 5-HT2B receptor agonist; 1–1000 _g/kg) produced dose-dependent increases in diastolic blood pressure and not dose-dependent increases in heart rate, while in pithed rats, these responses were attenuated. The vasopressor responses elicited by BW723C86 in anaesthetized rats were dose-dependently blocked by terguride (10–300_g/kg), whereas its the tachycardic responses were dose-independently blocked. These results, taken together, suggest that terguride behaved as an antagonist at the 5-HT2 receptors located in the central nervous system and (or) the systemic vasculature. This is the first evidence demonstrating that terguride can block central/peripheral 5-HT2 receptors mediating cardiovascular responses in anaesthetized or pithed rats.

Original languageEnglish
Pages (from-to)511-521
Number of pages11
JournalCanadian Journal of Physiology and Pharmacology
Volume98
Issue number8
DOIs
StatePublished - 2020

Keywords

  • 5-HT2 receptors
  • Anaesthetized rats
  • BW723C86
  • Pithed rats
  • Terguride

Fingerprint

Dive into the research topics of 'Blocking properties of terguride at the 5-ht2 receptor subtypes mediating cardiovascular responses in the rat'. Together they form a unique fingerprint.

Cite this