Biphasic Effects of D3-Receptor Agonists, 7-OH-DPAT and PD128907, on the D1-Receptor Agonist-Induced Hyperactivity in Mice

• Published in: Japanese journal of pharmacology Vol. 73; no. 3; pp. 251 - 254
• Main Authors: Mori, Tomohisa, Murase, Kenshi, Tanaka, Jiro, Ichimaru, Yasuyuki
• Format: Journal Article
• Language: English
• Published: Japan 1997
• Subjects: Analysis of Variance; Animals; Benzazepines - administration & dosage; Benzazepines - pharmacology; Benzopyrans - administration & dosage; Benzopyrans - pharmacology; D1-receptor agonist; D3-receptor agonist; Dopamine Agonists - administration & dosage; Dopamine Agonists - pharmacology; Dose-Response Relationship, Drug; Drug Interactions; Male; Mice; Motor activity; Motor Activity - drug effects; Oxazines - administration & dosage; Oxazines - pharmacology; Receptors, Dopamine D1 - agonists; Receptors, Dopamine D2 - agonists; Receptors, Dopamine D3; Receptors, Opioid, kappa - agonists; Tetrahydronaphthalenes - administration & dosage; Tetrahydronaphthalenes - pharmacology; D3-receptor agonist; Motor activity; D1-receptor agonist
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1254/jjp.73.251

Effects of D3-receptor agonists, 7-OH-DPAT and PD128907, on the D1-receptor agonist SKF81297-induced hyperactivity in mice were examined. 7-OH-DPAT and PD128907 significantly suppressed the SKF81297-induced hyperactivity at low doses, but significantly potentiated the hyperactivity at high doses. These D3-agonists alone had no effect on the motor activity. A κ-receptor agonist that reduces dopamine release had no effect on the SKF81297-induced hyperactivity. These results suggest that lower doses of 7-OH-DPAT and PD128907 may negatively influence the D1-receptor mediated behaviors via post synaptic D3-receptors. On the other hand, higher doses of these compounds may positively influence these behaviors via D2- or D3-receptors.