Involvement of central beta-adrenoceptors in the regulation of yawning responses.
A behavioral study was performed in an attempt to understand the role of central beta-adrenoceptors in yawning in rats. Yawning was evoked by apomorphine and piribedil, mixed dopamine D1/D2-receptor agonists, but not by SK&F 38393 [1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol], a dopamine D1-receptor agonist. The apomorphine-induced yawning was increased by pindolol, propranolol, indenolol, alprenolol and bukumolol which block the central beta-adrenoceptors, but not by the peripheral beta-adrenoceptor antagonists, carteolol and atenolol. These beta-adrenoceptor antagonists given alone did not elicit yawning. Conversely, the yawning was inhibited by salbutamol, a beta-adrenoceptor agonist, without being affected by prazosin, an alpha-adrenoceptor antagonist. The combined administration of SK&F 38393 and the beta-adrenoceptor antagonists did not induce yawning. The yawning elicited by either apomorphine or piribedil in combination with pindolol was suppressed by spiperone and YM-09151-2 [cis-N-(1-benzyl-2-methyl-pyrrolidin-3-yl)-5- chloro-2-methoxy-4-methylamino-benzamide], dopamine D2-receptor antagonists, and scopolamine, a muscarinic receptor antagonist, but not by SCH 23390 [R(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3- benzazepine-7-ol], a dopamine D1-receptor antagonist. Physostigmine or pilocarpine induced yawning, which was also enhanced by pindolol and propranolol. This enhanced yawning was inhibited by scopolamine, but not by spiperone, YM-09151-2 and SCH 23390.(ABSTRACT TRUNCATED AT 250 WORDS)
Yamada
K
K
Department of Pharmacology, Research Laboratory of Biodynamics, School of Medicine, Fukuoka University, Japan.
Matsumoto
S
S
Nagashima
M
M
Kumagai
M
M
Kimura
H
H
Furukawa
T
T
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D015259:Dopamine Agents / Q000494:pharmacology; D008297:Male; D010277:Parasympathomimetics / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D013565:Sympatholytics / Q000494:pharmacology; D013566:Sympathomimetics / Q000494:pharmacology; D015000:Yawning / Q000187:drug effects*
D000319:Adrenergic beta-Antagonists; D015259:Dopamine Agents; D010277:Parasympathomimetics; D011943:Receptors, Adrenergic, beta; D013565:Sympatholytics; D013566:Sympathomimetics; D001058:Apomorphine