Details

Autor(en) / Beteiligte

• White, Paul J.
• Rose'Meyer, Roselyn B.
• Hope, Wendy

Titel

Functional characterization of adenosine receptors in the nucleus tractus solitarius mediating hypotensive responses in the rat

Ist Teil von

• British journal of pharmacology, 1996-01, Vol.117 (2), p.305-308

Ort / Verlag

Oxford, UK: Blackwell Publishing Ltd

Erscheinungsjahr

1996

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• 1 The aim of this study was to characterize adenosine receptors located in the nucleus tractus solitarius (NTS) that mediate decreases in blood pressure in the anaesthetized rat. To determine the adenosine receptor subtype involved, a range of selective agonists and antagonists were studied and their relative potencies evaluated. 2 The rank order of agonist potency in inducing decreases in diastolic blood pressure was N6‐ cyclopentyladenosine (CPA)> N6‐cyclohexyladenosine (CHA)> N‐ethyl‐carboxamidoadenosine (NECA)≥ 2‐phenylaminoadenosine (CV1808)> 2‐p‐(carboxyethyl) phenethylamino‐5′ N‐ethylcarboxamidoadenosine (CGS 21680)> N6−(2−(4‐aminophenyl)ethyl)‐adenosine (APNEA). 3 The hypotensive action of CPA following microinjection into the NTS was antagonized by i.v. infusions (50 μg kg−1 min−1) of adenosine receptor antagonists, 8‐cyclopentyl‐1,3 dipropylxanthine (DPCPX), 8‐phenyltheophylline (8‐PT), 8‐(p‐sulphophenyl)theophylline (8‐SPT), and 1,3‐dipropyl‐8‐N‐(2‐(diethylamino)ethyl)‐N methyl‐4‐(2,3,6,7‐tetrahydro‐2,6‐dioxo) benzenesulphonamidexanthine (PD 115199). The antagonist potency order was DPCPXPD1151998‐PT. Intravenous infusion of 8‐SPT had no effect on blood pressure responses to microinjection of CPA into the NTS. 4 The results suggest that adenosine A1 receptors in the NTS mediate hypotensive responses in the anaesthetized rat preparation.