Ion content of synaptic vesicles.

Proton induced X-ray emission analysis measurements were performed to determine the P, S, K, Ca Fe, Ni, Cu and Zn ion content of presynaptic vesicles prepared from guinea-pig brain cortex. The number of different ions per single vesicle is calculated using the results of the additional protein content determinations. The ion contents of cholinergic and adrenergic vesicles are compared.