Decreased analgesic effect of morphine, but not buprenorphine, in patients with advanced P-glycoprotein(+) cancers.
Journal Title: Pharmacological Reports - Year 2012, Vol 64, Issue 4
Abstract
Background: P-glycoprotein (P-gp) is expressed on the blood-brain barrier (BBB) and acts as a transporter regulating the analgesic effect of morphine. The P-gp is also expressed by different types of tumors. The aim of this study was to determine the potential association of the P-gp expression in malignant tumors with analgesic effects in patients. Methods: The P-gp expression in 120 malignant tumors was examined by immunohistochemistry. The analgesic responses of individual patients to morphine and buprenorphine (BNP) were evaluated by visual analog scale (VAS). The levels of plasma morphine and BNP were determined by HPLC. Results: We found that there was no significant difference in the values of VAS between patients with P-gp(+) and P-gp(-) malignant tumors in responses to 0.000025 g x kg(-2) of BNP administered by patient-controlled intravenous analgesia (PCIA), accompanied by similar levels of plasma BNP in those patients. In contrast, the values of VAS in response to 0.00075 g x kg(-2) of morphine in patients with P-gp(+) tumors were significantly greater than those in the patients with P-gp(-) tumors, although similar levels of plasma morphine were detected in both groups of patients. Furthermore, treatment with a higher dose (0.0011 g x kg(-2)) of morphine effectively controlled pain in those with P-gp(+) tumors. Conclusion: Our data indicated that patients with P-gp(+) tumors required a higher dose of morphine to achieve an analgesic effect and that the P-gp expression in tumors may be valuable for predicting the analgesic responses of patients with severe pain to morphine.
Authors and Affiliations
Jun Wang, Bing Cai, Dong-Xiao Huang, Shu-Dong Yang, Lin Guo
Synergistic protective effect of picroside II and NGF on PC12 cells against oxidative stress induced by H(2)O(2).
Epidemiological studies suggest that nerve growth factor (NGF) is associated with a reduced risk of acute or chronic neuropathies. We studied the synergistic protective effect of picroside II and NGF against the oxidativ...
Prophylactic effect of lithium in bipolar affective illness may be related to serotonin transporter genotype.
Serotonin transporter promoter length polymorphism (5-HTTLPR) has been implicated in the pathogenesis of mood disorders and in the therapeutic response to serotonergic drugs. In this study, the 5-HTTLPR was estimated in...
Epicutaneous immunization with myelin basic protein protects from the experimental autoimmune encephalomyelitis.
Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system (CNS) with limited treatment modalities. One of the experimental methods that protect from autoimmune diseases is oral to...
Long-term use of low-dose spironolactone in spontaneously hypertensive rats: Effects on left ventricular hypertrophy and stiffness.
The aim of the present study was to evaluate the effect of low-dose spironolactone initiated during the early stages of hypertension development and to assess the effects of chronic pressure overload on ventricular remod...
Acute doxorubicin pulmotoxicity in rats with malignant neoplasm is effectively treated with fullerenol C60(OH)24 through inhibition of oxidative stress.
The aim of this study was to investigate the possible protective role of fullerenol (FLR, C(60)(OH)(24) on doxorubicin (DOX)-induced lung toxicity using biochemical and histopathological approaches. Rats (Sprague-Dawley...