ABSTRACT
1. The effect of titiyustoxin (TsTX) and ouabain on the incorporation of 32P into a protein of the same apparent molecular weight as synapsin I it described. 2. Tityustoxin-stimulated protein phosphorylation in a crude synaptosome fraction increased up to a concentration of 3.0 micron time of 15 s. 3. Trifluoperazizne (100 micronM) inhibited, while trifluoperazine sulphoxide (100 micronM) did not alter the effect on the protein phosphorylation induced by tityustoxin. 4. Unlike tityutixin, ouabain (100 micronM) hada no effect on protein phosphorylation even after incubation up to 20 min. 5. Ouabain at at 10 micronM, a concentration having no effect on rates of respiration and ATP hydrolysis in brain cortical slices, also had no effect on protein phosphorylation