Fig. 1.

Quinacrine fluorescent histochemistry showing quinacrine-positive intramural nerve cell bodies and varicose fibres in the guinea pig atrium. a A fine plexus of quinacrine-positive nerve fibres. b A similar preparation to a after treatment with 6-hydroxydopamine (one intraperitoneal injection, 250 mg/kg, 24 h prior to sacrifice). c A cardiac ganglion showing 20–30 quinacrine-positive nerve cell bodies; d Another ganglion, containing a smaller proportion of quinacrine-positive cell bodies. All bars represent 100 μm (reproduced from [6], with permission)