Action of 1,10-phenanthroline transition metal chelates and their constituents on the rat isolated diaphragm preparation.
The actions of two related series of fully co-ordinated, divalent 1,10-phenanthroline transition metal chelates have been investigated on the rat isolated diaphragm muscle-phrenic nerve preparation and, where possible, compared with those of their constituent metal ions and ligands. Each member of both series of chelates produced blockade of neuromuscular transmission, although mechanistically not of a uniform type, and several elicited varying degrees of muscle contracture. The kinetic reactivity of the metal chelate appeared to be an important factor determining the nature of the biological response and profound differences in response were observed between labile and inert chelates differing in some cases by only one electron in the 3d shell.