The effect of calcium, neostigmine and 4-aminopyridine upon respiratory arrest and depression of cardiovascular functions after aminoglycosidic antibiotics.

Neomycin causes arrest of peripheral respiration by blocking neuromuscular transmission by a presynaptic mechanism. It is not effective in the postsynaptic region until 14fold concentrations are used and it acts by a mechanism different from that of d-tubocurarine. Besides this, it has cardio-depressive effects. The common action of neomycin in all systems apparently concerns the movement of calcium across cell membranes. Calcium and 4-amino-pyridine act as antagonists of the curare-like activities of neomycin and its cardio-depressive action. Neostigmine is not an antagonist of these side-effects. 4-Aminopyridine is effective even in the case of calcium resistance which occurs after combination of several drugs related to neuromuscular transmission and neomycin.