Central action of acidic fibroblast growth factor in feeding regulation

A phasic increase in activity similar to that of acidic fibroblast growth factor (aFGF) was detected in the cerebrospinal fluid of rats after feeding or after an intraperitoneal injection of glucose. This FGF-like activity in the cerebrospinal fluid was bioassayed in two systems: depression of the feeding response of Hydra and DNA synthesis-stimulating activity in BALB/c 3T3 cells after fractionation on a heparin affinity column. Dynamic feeding-related changes in activity of aFGF, basic FGF, and other growth factors were detected by both bioassay systems. Intracerebroventricular microinfusion of aFGF suppressed food intake in rats. Central infusion of inactivated aFGF, or peripheral administration of aFGF, in doses equivalent to or higher than those administered centrally was without effect. Electrophoretically applied aFGF specifically suppressed the activity of glucose-sensitive neurons in the lateral hypothalamus. Glucose-insensitive neurons were only slightly affected. The results suggest that aFGF may participate in the regulation of feeding at the level of the central nervous system.