M5 Muscarinic Receptors Mediate Striatal Dopamine Activation by Ventral Tegmental Morphine and Pedunculopontine Stimulation in Mice
Figure 1
VTA injection sites (A) and nucleus accumbens recording sites (B) used in Experiment 1.
In both (A) and (B), open circles show placements from M5 knockout mice (n = 4) treated with 50 ng intra-VTA morphine, closed circles show placements from M5 knockout mice treated with 0.3 µl intra-VTA saline (n = 4), open triangles show placements from wildtype mice (n = 4) treated with 50 ng intra-VTA morphine, closed triangles show placements from wildtype mice (n = 4) treated with 0.3 µl intra-VTA saline, stars show placements from wildtype mice (n = 6) pre-treated with 50 µg intra-VTA scopolamine followed by 50 ng intra-VTA morphine, and open squares show placements from wildtype mice (n = 4) pre-treated with 1 mg/kg (i.p.) naltrexone followed by 50 ng intra-VTA morphine. For clarity infusion sites are shown on both left and right side of the brain, but VTA infusions were always made on the left side of the brain. Numbers to the left of or above individual sections show distance in mm from bregma. Sections were adapted from the atlas of Paxinos and Franklin [38].