Competition between lever-pressing behavior and thermoregulatory behavior on exposure to heat in intracranial self-stimulating rats.
To investigate the relationship between the thermoregulatory system and the brain-reward system, we examined effects of heat exposure and tail amputation on lever-pressing behavior in intracranial self-stimulating rats. Rats that continuously pressed a lever voluntarily for 1 hour at an ambient temperature (Ta) of 22 degrees C interrupted lever pressing and showed heat loss behaviors, such as grooming and body extension, at a Ta of 36 degrees C. Hypothalamic temperature (Thy) at the time of the first body extension was higher than that after 1 hour of lever-pressing at a Ta of 22 degrees C. Tail amputation experiments showed the same result. Thy at the onset of the body extension after tail amputation was higher than that at the end of 1 hour of lever-pressing under control conditions. The data suggest that thermal factors, especially Thy, are important in the control of lever-pressing behavior.
Ishikawa
Y
Y
Department of Physiology, Osaka University Medical School, Japan.
Tanaka
H
H
Nakayama
T
T
Kanosue
K
K
D000671:Amputation, Surgical; D000818:Animals; D001522:Behavior, Animal; D001833:Body Temperature Regulation; D006358:Hot Temperature; D007858:Learning; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012653:Self Stimulation; D013623:Tail