EVIDENCE THAT HEMOLYMPH GLUCOSE IN APLYSIA-CALIFORNICA IS REGULATED BUT DOES NOT AFFECT FEEDING-BEHAVIOR

Hemolymph glucose increased following a meal of a commercially availab le dried seaweed (laver) in Aplysia californica (Aplysia). Glucose inj ected into the hemocoel did not affect meal size, bite latencies, swal lowing rate, or 24-hr food intake. The authors found that injection of a homogenate of nerves containing a putative Aplysia insulin-like sub stance decreased hemolymph glucose. The nerve homogenate, however, did not affect feeding behavior. Injection of 2-deoxy-D-glucose was found to increase hemolymph glucose, an indication of gluco-privation, but instead of increasing feeding it either had no effect or, at high dose s, debilitated animals and interfered with feeding. These studies sugg est that glucose may be physiologically regulated in Aplysia, but it d oes not appear to play a role in the control of feeding behavior.