Administration of leu-enkephalin impairs the acquisition of preference for ethanol.
The effects of subcutaneous administration of leu-enkephalin (LEU-E) (10, 100 and 300 micrograms/kg) and LEU-E (100 micrograms/kg) plus naloxone (2.5 mg/kg) on ethanol preference and fluid intake have been investigated in rats. Under our procedural conditions, rats develop ethanol preference through forced ethanol drinking (conditioning session). Preconditioning administration of LEU-E induced a reduction of later ethanol preference. Post-conditioning administration of LEU-E (10 and 100 micrograms/kg) also attenuated the development of ethanol preference. NX antagonized the effects of LEU-E on ethanol preference and fluid consumption in the two experimental procedures used, indicating an involvement of opioid receptors in the LEU-E-induced impairment of the acquisition of ethanol preference.
Sandi
C
C
Department of Psychobiology, Cajal Institute, Madrid, Spain.
Borrell
J
J
Guaza
C
C
D000428:Alcohol Drinking / Q000187:drug effects*; D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D004743:Enkephalin, Leucine / Q000494:pharmacology*; D000431:Ethanol / Q000494:pharmacology*; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D009270:Naloxone; D000431:Ethanol; D004743:Enkephalin, Leucine