Effect of NMDA receptor antagonist on naloxone-precipitated withdrawal signs in cholestatic mice.
The ability of NMDA antagonist MK-801 to block the expression of opioid-like withdrawal signs was examined in bile duct-ligated mice and the signs were compared with sham operated and unoperated animals. Administration of MK-801 (0/1 mg/kg), 10 min prior to naloxone challenge, significantly reduced the investigated withdrawal signs (jumping, diarrhoea, grooming and climbing) in bile duct-ligated animals. Chronic administration (five consecutive days) of MK-801 (0/1 mg/kg) also decreased all the withdrawal signs in the experimental animals. In an independent series of experiments, the effect of acute and chronic administration of MK-801 on tail-flick latency was investigated in bile duct-ligated animals. Pretreatment with the drug significantly decreased the antinociception induced by bile duct ligation in the mice. The results of this study support evidence for the involvement of the NMDA receptor in yopioidergic-dependent manifestations in a model of obstructive cholestasis. Copyright 2000 John Wiley & Sons, Ltd.
Dehpour
Ahmad Reza
AR
Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Samini
Morteza
M
Rastegar
Hossein
H
Ardeshiri
Abazar Jamshidi
AJ
Roushanzamir
Farshad
F
Jorjani
Masoumeh
M
Ahmadiani
Abolhassan
A