Long-lasting effects of the noradrenergic neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) on prevertebral sympathetic neurones in the rat.

Following intraperitoneal administration of the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) in rats, the irides and pieces of jejunum were treated by the glyoxylic acid method in order to reveal their adrenergic nerves. Seven days after the injection, the fluorescence of adrenergic nerves in the iris was partly restored and by 35 days was indistinguishable in density and brightness from controls. In contrast, even 118 days post-injection, the adrenergic component of Auerbach's plexus of the jejunum was still markedly affected by the DSP-4. The regeneration was incomplete, giving a patchy appearance, and less fluorescent than the controls. It is suggested that, when injected intraperitoneally, DSP-4 can have more potent effects than hitherto realised.