Chlorpromazine specifically prevents the wheel-induced feeding suppression in rats

In rats, limited daytime wheel access suppresses feeding over the subsequent night [Lattanzio SB, Eikelboom R. Wheel access duration in rats: I. effects on feeding and running. Behav Neurosci 2003; 117:496-504.]. This phenomenon is known as the wheel-induced feeding suppression (WIFS). The classic antipsychotic, chlorpromazine, can minimize the severity of the related activity anorexia procedure, but is thought to act through a suppression of running [Routtenberg A. “Self-starvation” of rats living in activity wheels: adaptation effects. J Comp Physiol Psychol 1968; 66:234-8.]. We tested the effects of chlorpromazine (2 mg/kg IP) on the acute WIFS in 40 adult male rats by administering the drug before or after 3 h of daytime wheel access and measuring food consumption over the subsequent 24 h. Control groups received saline injections or were exposed to locked wheels. While chlorpromazine did not attenuate feeding or change wheel running alone, it blocked their interaction, the acute WIFS. This procedure might be useful in screening drugs for anorexia nervosa where exercise is often elevated and feeding is suppressed.