METHAMPHETAMINE IMPAIRS VISUAL AND PLACE MEMORY AND DEPLETES BRAIN MONOAMINES IN FEMALE RATS

M. GORDON; R. JONES; V.N. LUINE; V. BISAGNO

New Orleans, Louisiana, USA

Congreso; 2003 SFN Meeting; 2003

SFN

METHAMPHETAMINE IMPAIRS VISUAL AND PLACE MEMORY AND DEPLETES BRAIN MONOAMINES IN FEMALE RATS. V.N.Luine*; M.Gordon; R.Jones; V.Bisagno Dept. Psychol, Hunter Col, New York, NY, USA We previously reported that a neurotoxic regimen of methamphetamine (MA, 3 x 10 mg/kg) given to male rats was associated with less activity and enhanced anxiety, impaired visual but not place memory, and depletions of striatal dopamine and serotonin at 5-12 days post MA (Brain Res. 940: 95, 2002). We subjected female rats to the same treatment and analyses. On the open field, locomotor and anxiety measures of MA females did not differ from controls. Effects on visual and place memory were tested using object recognition and placement with inter-trial delays between the sample and retention trial of 4 h (visual) and 1 h (place). In the sample trials for tasks, MA-treated and control females showed the same amount of exploration. During recognition/retention trials, the controls spent more time exploring the new object/location whereas the MA-treated females did not indicating impaired visual and spatial memory. In frontal cortex and striatum, MA treatment was associated with approximately 60% decreases in dopamine or its metabolite HVA. In the frontal cortex, serotonin and metabolite 5-HIAA were also decreased by 60%. These results show dramatic impairments in cognitive function and monoamine levels in female rats following a neurotoxic regimen of MA. Furthermore, when compared with previous studies in males, these results show that behavioral, cognitive and neurochemical responses to methamphetamine are sexually differentiated.Support Contributed By: R24 DA 12136 NIDA