Somata-selective lesions induced by cobaltous chloride: a parametric study.

Repeated injections of cobaltous chloride destroy neuronal somata while sparing fibers-of-passage. This effect is dose-dependent and excess cobalt destroys fibers-of-passage as well as somata. By manipulating the concentration and volume of cobaltous chloride injected into rat lateral geniculate nuclei, we defined a range of parameters producing highly selective destruction of somata for regions 1 mm in diameter or smaller.