Effects of dopamine, NMDA, opiate, and serotonin-related agents on acute methamphetamine-induced self-injurious behavior in mice

We examined the biochemical processes responsible for acute methamphetamine (MAP)-induced self-injurious behavior (SIB) in mice. In initial experiment s, a single dose of MAP (5, 10, or 15 mg/kg, IP) or an equivalent volume of saline was administered to male BALB/c mice. Acute MAP administration dose dependently increased the incidence of SIB (p < 0.05). In further experime nts, we evaluated the effects of SCH23390, sulpiride, MK-801, naloxone or 5 -hydroxy-L-tryprophan (5-HTP) on the incidence of acute MAP (15 mg/kg, IP)- induced SIB. Both SCH23390 (0.5 and 1.0 mg/kg, IP) and 5-HTP (100 and 200 m g/kg, IP) reduced the incidence of MAP-induced SIB (p < 0.05). MK-801 (0.12 5 and 0.25 mg/kg, IP) completely blocked the SIB induced by MAP (p < 0.001) . In contrast, neither sulpiride (25, 50, and 100 mg/kg, IP) nor naloxone ( 1, 5, and 10 mg/kg, IP) affected the incidence of MAP-induced SIB. It is co ncluded that dopamine D-1, NMDA, and serotonin neurotransmission may be inv olved in critical biochemical processes responsible for acute MAP-induced S IB. (C) 2000 Elsevier Science Inc.