Functional innervation of the lacrimal gland in the cat. Origin of secretomotor fibers in the lacrimal nerve.

Abstract

Because doubt about the innervation of the lacrimal gland exists, the present study was undertaken to determine the functional innervation of lacrimal gland cells. Lacrimal nerve action potentials, lacrimal cell membrane potentials, and the outflow of fluid from an excretory duct of the lacrimal gland were recorded before, during, and after stimulation of the sphenopalatine ganglion, preganglionic trunk of the superior cervical ganglion, and the distal and proximal cut ends of the lacrimal nerve. The results indicate that the lacrimal nerve as it approaches the lacrimal gland contains secretomotor fibers, which originate in the sphenopalatine but not in the superior cervical ganglion. It was also found that although electrical stimulation of the preganglionic sympathetic trunk occasionally produced a slight, transient change in outflow from the excretory duct, there was no evidence that such stimulation produced secretory potentials in the cells of the lacrimal gland.