Control of the Salivary Glands of Helisoma by Identified Neurones

The neural regulation of an exocrine gland was investigated at the level of identified effector neurones. The salivary gland neuroeffector system of Helisoma consists of a pair of acinous glands innervated by two symmetrically located, identified buccal ganglion neurones (4R and 4L). Neurones 4R and 4L usually are electrically coupled and display synchronous activity. Action potentials in these neurones elicit EPSPs and action potentials in epithelial cells of the salivary glands. Spontaneous miniature potentials similar to those seen at neuromuscular junctions can be recorded from many of the glandular cells. Neurones 4R and rL, and thus also salivary gland cells, can display bursts of action potentials phase-locked with those seen in buccal mass motoneurones during feeding.