The effect of a new amphibian peptide, Leu8phyllolitorin, on thermoregulation in the rat.

In this study we have examined the effect and the possible interaction of ICV injection of Leu8phyllolitorin and SC injection of naloxone on thermoregulation in fasted and fed rats at cold (4 degrees C) and ambient (22 degrees C) temperature. Central injection of Leu8phyllolitorin have been shown to produce hypothermia in animals exposed to a cold environment, but not in animals maintained at 22 degrees C. This suggests that the stressful situation of a cold temperature is an important factor in causing peptide hypothermia. Naloxone enhanced the hypothermic effect of Leu8phyllolitorin at 4 degrees C and 22 degrees C both in fasted and in fed rats, reflecting an opiate receptor interaction for this response.