[Pharmacological analysis of the role of central alpha-2 adrenergic and imidazoline receptors in mechanism of the hypotensive effect of clonidine in rats].
The role of alpha 2-adrenergic and imidazoline receptors in the hemodynamic response to clonidine (manifested by reduced arterial pressure, heart rate, and renal blood flow rate) was studied by injecting their antagonists with different affinity (yohimbine and idazoxan) into narcotized Sprague--Dawley rats. The local introduction (microinjection into rostral ventrolateral medulla) and systemic administration (intraperitoneal injection) of the drugs showed that the hemodynamic effect of clonidine is mediated predominantly by the central alpha 2-adrenergic receptors, rather than by the imidazoline receptors.
Kuz'min
A I
AI
Department of Fundamental Medicine, Moscow State University, Vorob'evy gory, Russia.
Lodygin
D N
DN
Kalenikova
E I
EI
Bychkova
E Iu
EIu
Khokhlova
O N
ON
Murashev
A N
AN
Medvedev
O S
OS
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000502:physiology*; D003000:Clonidine / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D019329:Idazoxan / Q000494:pharmacology; D007093:Imidazoles / Q000378:metabolism*; D054755:Imidazoline Receptors; D008297:Male; D008526:Medulla Oblongata; D008845:Microinjections; D051381:Rats; D017207:Rats, Sprague-Dawley; D018341:Receptors, Adrenergic, alpha-2 / Q000187:drug effects* / Q000502:physiology; D011955:Receptors, Drug / Q000037:antagonists & inhibitors / Q000187:drug effects* / Q000502:physiology; D012039:Regional Blood Flow / Q000187:drug effects; D012077:Renal Artery / Q000502:physiology; D014655:Vascular Resistance / Q000187:drug effects; D015016:Yohimbine / Q000494:pharmacology
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D000959:Antihypertensive Agents; D007093:Imidazoles; D054755:Imidazoline Receptors; D018341:Receptors, Adrenergic, alpha-2; D011955:Receptors, Drug; D015016:Yohimbine; D003000:Clonidine; D019329:Idazoxan