Quinacrine-binding nervous elements in intraocular grafts of intestinal smooth muscle tissue.

Quinacrine (QC) histofluorescence demonstrates a population of nerve fibres in the intestine that are probably non-adrenergic and non-cholinergic. To discover whether these nerves are intrinsic to the intestinal wall smooth muscle layers of distal ileum from foetal mice and foetal and adult rats were homologously transplanted to the anterior chamber of the eye of adult animals. Transplants were well organized although devoid of their normal extrinsic nervous connections. QC-positive beaded nerve terminals were found in the smooth muscle layers of the grafts and QC-positive cell bodies in Auerbach's plexus. Since QC-binding nerves are not normally present in the host iris it was concluded that the gut contains intrinsic QC-binding neurons.