gastropyloric nerve (sensu Cancer borealis)

The gastropyloric nerve in Cancer borealis consists of gastropyloric receptor (GPR) neurons, which are stretch-sensitive mechanoreceptors. GPR neurons innervate stomach muscles and monitor muscle tension and length during gastric and pyloric movements, providing sensory feedback to the stomatogastric circuit.

In Cancer borealis, the gastropyloric nerve runs from the stomach muscles to the stomatogastric nervous system. GPR neurons have sensory endings embedded within the muscle fibers of the gastric mill and pyloric regions, with axons that project centrally to the stomatogastric ganglion and commissural ganglia.

The gastropyloric nerve is involved in providing sensory feedback from stomach muscles to the stomatogastric circuit. GPR neurons are stretch receptors that respond to muscle movement and tension. Their activation during stomach contractions can modulate the gastric mill rhythm and influence the timing and amplitude of motor output from the stomatogastric ganglion.

Experimental manipulations such as stretching or contracting stomach muscles, pharmacological application of modulatory substances to GPR neuron receptive fields, or severing the afferent connections of GPR neurons may be associated with altered sensory feedback and changed motor circuit dynamics. The role of GPR neurons is studied in the context of sensory-motor integration.

GPR neurons within the gastropyloric nerve are studied using electrophysiological techniques, including extracellular recordings from the nerve and intracellular recordings from individual GPR neuron somata. Mechanical stimulation of the stomach muscles while recording allows study of their stretch sensitivity. Immunohistochemistry and dye fills characterize the morphology and neurochemistry of GPR neurons.