Comparison of the effects of MnPO4 on striatal DA and Dopac levels with the effects of cobalt and zinc phosphate. Striatal slices from male Sprague Dawley rats were collected and incubated for 4 h either in control medium or in medium containing MnPO4, ZnPO4, or CoPO4 at 1, 10, or 100 μM concentrations each. Tissue levels of DA (Fig. 4a), media levels of DA (Fig. 4b) and media levels of Dopac (Fig. 4c) were analyzed by HPLC-ECD and the data was subsequently normalized on a per mg of protein basis and expressed as a percent of vehicle control. *, **, *** Presence and number of asterisks indicate significant differences (P ≤ 0.05).