Autonomic and sensory innervation of anuran ultimobranchial glands: a horseradish peroxidase study.

ABSTRACT

The extrinsic innervation of the endocrine ultimobranchial glands in the frog were identified by retrograde labeling with horseradish peroxidase. Labeled neurons were seen ipsilateral to the side injected in the caudal region of the vagal motor nucleus, the jugular sensory ganglion and first and second cervical sympathetic ganglia. These studies demonstrate a dual autonomic and vagal sensory innervation of the gland that are compatible with previous ultrastructural studies, but indicate a more complex innervation than previously shown.