Autonomic Innervation of the Cat Iris

An identification of individual adrenergic and cholinergic nerve terminals would appear to be possible at the ultrastructural level. It is submitted that there exists a significant dual innervation of the feline dilator muscle and to a lesser extent a dual innervation of the feline sphincter muscle. Selective degeneration experiments have been performed showing a rapid degeneration of the specific nerve terminals with sparing of the unaffected fibers.