TY - JOUR
T1 - Effects of morphine and clonidine on sulphobromophthalein disposition in mice
AU - Ben‐Zvi, Zvi
AU - Hurwitz, Aryeh
PY - 1986/6
Y1 - 1986/6
N2 - Levels of sulphobromophthalein (BSP) in plasma and liver were elevated by the opiate, morphine, and by the α2‐adrenoceptor agonist, clonidine. Neither morphine, 1 mg kg−1, nor clonidine, 0.01 mg kg−1, affected BSP levels significantly. When given together at these doses, they caused BSP levels in plasma and liver to be raised. At 20 mg kg−1, the effect of morphine on BSP levels was maximal, as was that of clonidine, 1.0 mg kg−1. However, the effect of these drugs given together on plasma BSP exceeded the maximal effect of either alone. Yohimbine, an α2‐adrenoceptor antagonist, did not affect BSP levels, nor did the opiate antagonist, naloxone. Each of these antagonists reversed the hepatobiliary effects of its respective agonist, as shown by return of BSP levels to those of saline‐treated mice. Yohimbine did not reverse morphine, nor did naloxone reverse clonidine. The additive effects of morphine and clonidine and the specificities of their respective antagonists strongly suggest the involvement of discrete receptors mediating their essentially identical hepatobiliary effects.
AB - Levels of sulphobromophthalein (BSP) in plasma and liver were elevated by the opiate, morphine, and by the α2‐adrenoceptor agonist, clonidine. Neither morphine, 1 mg kg−1, nor clonidine, 0.01 mg kg−1, affected BSP levels significantly. When given together at these doses, they caused BSP levels in plasma and liver to be raised. At 20 mg kg−1, the effect of morphine on BSP levels was maximal, as was that of clonidine, 1.0 mg kg−1. However, the effect of these drugs given together on plasma BSP exceeded the maximal effect of either alone. Yohimbine, an α2‐adrenoceptor antagonist, did not affect BSP levels, nor did the opiate antagonist, naloxone. Each of these antagonists reversed the hepatobiliary effects of its respective agonist, as shown by return of BSP levels to those of saline‐treated mice. Yohimbine did not reverse morphine, nor did naloxone reverse clonidine. The additive effects of morphine and clonidine and the specificities of their respective antagonists strongly suggest the involvement of discrete receptors mediating their essentially identical hepatobiliary effects.
UR - http://www.scopus.com/inward/record.url?scp=0022460292&partnerID=8YFLogxK
U2 - 10.1111/j.2042-7158.1986.tb04617.x
DO - 10.1111/j.2042-7158.1986.tb04617.x
M3 - Article
C2 - 2873230
AN - SCOPUS:0022460292
SN - 0022-3573
VL - 38
SP - 481
EP - 483
JO - Journal of Pharmacy and Pharmacology
JF - Journal of Pharmacy and Pharmacology
IS - 6
ER -