Dopamine D-1 but not D-2 receptor stimulation of the dorsal striatum potentiates apomorphine-induced jaw movements in rats.
The effects of bilateral injections of selective D-1 and D-2 agonists and antagonists into the dorsal striata on apomorphine-induced jaw movements were studied in ketamine-anaesthetized rats after C1 spinal transection. A phototransducer attached to the lower mandible automatically detected jaw movements. YM-09151-2 (0.2 and 0.5 micrograms) and cis(Z)-flupentixol (0.5 and 1 microgram) injected into the dorsal striatum increased the frequency of jaw movements after apomorphine (0.2 mg/kg i.v.). The effects were prevented by administration of SCH23390 (1 microgram) with YM-09151-2 (0.5 microgram) or cis(Z)-flupentixol (1 microgram). Injection of SCH23390 (1 microgram) alone into the dorsal striatum failed to alter the apomorphine (0.5 mg/kg i.v.)-induced jaw movements. Local application of the selective D-1 agonists, SKF38393 (5 micrograms) and SKF75670 (10 micrograms), into the dorsal striatum potentiated the apomorphine (0.2 mg/kg i.v.)-induced jaw movements, while a D-2 agonist, quinpirole (10 micrograms), injected into the same site attenuated these movements. These data are suggestive of an oppositional D-1: D-2 receptor interaction in the dorsal striatum.
Koshikawa
N
N
Department of Pharmacology, Nihon University School of Dentistry, Tokyo, Japan.
Tomiyama
K
K
Omiya
K
K
de Beltrán
K K
KK
Kobayashi
M
M
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D015259:Dopamine Agents / Q000494:pharmacology*; D018492:Dopamine Antagonists; D007267:Injections; D007568:Jaw / Q000502:physiology; D008297:Male; D009068:Movement / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects / Q000378:metabolism*; D013469:Sulpiride / Q000494:pharmacology
D001552:Benzazepines; D015259:Dopamine Agents; D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; C052506:SK&F 75670; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D013469:Sulpiride; D001058:Apomorphine