EVIDENCE FOR SPECIFIC INVOLVEMENT OF DOPAMINE D(1) AND DOPAMINE D(2) RECEPTORS IN THE REGULATION OF BODY-TEMPERATURE IN THE RAT

Administration of the selective dopamine D1 and D2 receptor agonists, A 68930 (0.9-60.0 mumol kg-1 s.c.) and quinpirole (0.1-6.0 mumol kg-1 s.c.), produced a dose-dependent decrease in core temperature in the r at. The hypothermia induced by quinpirole (1.5 mumol kg-1) was antagon ized by pretreatment with the selective dopamine D2 receptor antagonis t, raclopride (1.6 mumol kg-1 s.c.), but not by the dopamine D1 recept or antagonist, SCH 23390 (0.3 mumol kg-1 s.c.), whereas the hypothermi a induced by A 68930 (3.8 mumol kg-1) was antagonized by SCH 23390 (0. 3 mumol kg-1), but not by raclopride (1.6 mumol kg-1). Together, these results suggest that both dopamine D1 and D2 receptors are specifical ly involved in the regulation of body temperature in the rat.