Figure 5.
Ablation of striatal neurokinin-1 receptor-expressing interneurons prevented methamphetamine-induced cell death in the striatum. Animals received intrastriatal injections of SSP-SAP [4ng, 1 ul volume] into one striatum (B, D & F) and saporin (SAP) [4ng, 1 ul volume] into the contralateral side (A, C & E). Three weeks after the injections, the animals received a single intraperitoneal injection of METH (30 mg/kg). The animals were then sacrificed one day after METH treatment. Striatal sections were processed for immunofluorescence using TUNEL and an antibody against the neurokinin-1 receptor. White square indicates region devoid of neurokinin-1 receptor immunofluorescence. Local ablation of striatal neurokinin-1 receptor-expressing interneurons conferred protection from METH-induced cell death on the ipsilateral side (B, D and F). No protection was observed on the contralateral side receiving only SAP (A, C and E). White arrows show representative TUNEL-positive cells. Magnification bars are 250 μm (A & B) and 50 μm (C, D, E & F). cc = corpus collasum.