Prostaglandin E1 may Act as a “Calcium Ionophore”

MUCH of the pharmacology of the prostaglandins (PG) could be interpreted in terms of their facilitation of the movement of calcium ions into or out of biological membranes¹. We have therefore investigated this possibility, taking advantage of the configurational changes and attendant changes in light-scattering which result from the binding of calcium ions to the mitochondrial inner membrane². Preliminary findings, which we report here, provide evidence of a marked facilitation of non-energized binding of calcium to mitochondrial membranes when in the presence of PGE₁ at concentrations of the order of 10^?7 M.