Catecholaminergic alpha-receptors and shivering in the rat.
1. A rise or a fall in systemic blood pressure brought about by the I.V. infusion of peripherally acting drugs (adenosine, noradrenaline or methoxamine) inhibited shivering in the cold-exposed rat. 2. Since the injection of commonly used doses of noradrenaline (0.05-0.10 mumole) into a lateral cerebral ventricle of a rat was usually accompanied by a rise in blood pressure special precautious were required to determine whether noradrenaline had a specific central effect on shivering. 3. Small doses of noradrenaline (0.02-0.03 mumole) or clonidine (0.01 mumole) which had no effect on blood pressure when injected into a lateral cerebral ventricle still inhibited shivering in the cold-exposed rat and this effect was prevented by phentolamine. 4. It is concluded that noradrenaline can inhibit the cold sensor-shivering pathway in its central course by an action on alpha-receptors.
D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003000:Clonidine / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D008729:Methoxamine / Q000494:pharmacology; D009434:Neural Pathways / Q000187:drug effects; D009638:Norepinephrine / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D011941:Receptors, Adrenergic / Q000502:physiology*; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D012768:Shivering / Q000187:drug effects
D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D008729:Methoxamine; D000241:Adenosine; D003000:Clonidine; D009638:Norepinephrine