“…Mongar (1970) found that strontium will replace calcium in chopped guinea-pig lung, and that magnesium-and barium antagonize this effect of calcium. Strontium and barium replace calcium in the activation of histamine release induced by compound 48/80 in the perfused cat paw (Strandberg, 1971). J. C. FOREMAN AND J. L. MONGAR There have been several studies of the antagonism between calcium and magnesium at the neuromuscular junction (Jenkinson, 1957;Dodge & Rahamimoff, 1967;Bloich, Glagoleva, Liberman & Nenashev, 1968), and strontium is able to substitute for calcium in the activation of transmitter release at the neuromuscular junction (Miledi, 1966;Dodge, Miledi & Rahmamimoff, 1969).…”