The brain Renin- Angiotensin System (RAS) is involved in the neuroadaptative responses induced by amphetamine in a two-injection protocol.

PAZ, M. C.; MARCHESE, N.; STROPPA, M; IMBODEN, H.; CANCELA, L. M.; BREGONZIO, C.

Huerta Grande, Córdoba, Argentina

Congreso; XXVI Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias; 2011

Sociedad Argentina de Investigación en Neurociencias

A single o repeated exposure to psychostimulants induces long-lasting neuroadaptatives changes. Different neurotransmitter systems are involved in these repsonses including the neuropeptide angiotensin II. Our study tested the hypotesis that the neuroadaptative changes induced by AMPH produce alterations in brain RAS components. Wistar male rats (250-300g), pretreated with AMPH (5 mg/kg, ip) were used 7 or 21 days later to quantified AT1 receptors by western blot and mRAN-Angiotensinogen (AOGEN)in caudate putamen (CPu) and accumbens nucleus (NAcc). In another group of animals treated in the same way, bearing intra-cerebral cannula, the locomotor activity was tested after AMPH challenge (0.5 mg/kg) injection. the animals recieved an AT1 blocker, losartan (8 ug/ul/side)or saline 5 min before the AMPH challenge. We found and increse of AT1 receptor density in both studied areas. AMPH modifed the basal and challenge induced expression of mRNA-AOGEN in NAcc and CPu at 7 and 21 days after tratment. Finally the AT1 receptors blockade in NAcc increased the locomotor activity induced by AMPH challenge. Our results support the hypotesis for a key role of brain RAS in neuroadaptative changes induced by AMPH.