Primary investigation on heterodimerization of kappa-opioid receptor and ORL1 receptor / 药学学报

This study investigates whether kappa-opioid receptor and ORL1 receptor may interact to form a heterodimer. In immunofluorescence and co-immunoprecipitation experiments, differentially epitope-tagged receptors, colocalization and heterodimerization of kappa-opioid receptor and ORL1 receptor were used and examined in primary culturing rat neurons, Chinese hamster ovary (CHO) or human embryonic kidney 293 (HEK293) cells. The results show that fluorescence of both kappa-opioid receptor and ORL1 receptor were overlapping in primary culturing hippocampal and cortical neurons. Similarly in co-expressing CHO or HEK293 cells, HA-KOR and Myc-ORL1 were almost exclusively confined to the membranes, revealing extensive colocalization. When Flag-KOR and Myc-ORL1 were co-expressing in CHO cells, heterodimerization was identified to have the ability to co-immunoprecipitate ORL1-receptors with kappa-opioid receptor and vice versa. In the current study, further evidence was provided for the direct interaction of two subtypes of opioid receptors, kappa-opioid receptor and ORL1-receptor, to form the heterodimerization. The finding represents the novel pharmacological mechanism for modulation of opioid receptor function as well as diversity of G protein-coupled receptors.

Pharmacokinetics of 6beta-naltrexol after single and multiple intramuscular injections in Beagle dogs / 药学学报

The pharmacokinetics of 6beta-naltrexol (6beta-NOL) following single intramuscular administration and multiple intramuscular injection once per day for seven days was studied in 4 Beagle dogs. Plasma concentration of 6beta-NOL in dogs was analyzed by a combination of high performance liquid chromatography (HPLC) and electrochemical detection with naloxone (NLX) as internal standard. After single intramuscular injection of 0.2 mg x kg(-1) 6beta-NOL, the plasma concentration-time curve of the drug was found to fit to a two compartment model with first-order absorption. The main parameters of single dosing were as follows: t1/2alpha was (0.26 +/- 0.23) h, t1/2beta was (4.77 +/- 1.65) h, C(max) was (81.65 +/- 5.61) ng x mL(-1), t(peak) was (0.27 +/- 0.07) h, CL(s) was (1.20 +/- 0.06) L x kg(-1) x h(-1), V/F(c) was (1.94 +/- 0.15) L x kg(-1), and AUC(0-t) was (166.82 +/- 7.68) ng x h x mL(-1), separately. After multiple intramuscular injection of 0.2 mg x kg(-1) 6beta-NOL once per day for seven days, the plasma concentration-time curve of the drug fitted to a two compartment model with first-order absorption too. The main parameters of the last dosing were as follows: t1/2alpha was (0.19 +/- 0.18) h, t1/2beta was (5.79 +/- 1.50) h, C(max) was (79.82 +/- 10.5) ng x mL(-1), t(peak) was (0.18 +/- 0.08) h, CL(s) was (1.12 +/- 0.07) L x kg(-1) x h(-1), V/F(c) was (2.10 +/- 0.27) L x kg(-1), and AUC(0-t) was (173.23 +/- 9.49) ng x h x mL(-1), separately. The difference of the parameters between the first and the last dosing was not significant, showing that the plasma kinetics of 6beta-naltrexol was not changed after multiple administrations. In the course of multiple administration, the peak and valley concentration of plasma 6beta-naltrexol were (79.03 +/- 10.3) and (1.50 +/- 0.93) ng x mL(-1), respectively. No clear adverse events were noted during this study. These results showed that plasma 6beta-naltrexol fits to a two compartment model with first-order absorption in dog after intramuscular administration and their pharmacokinetic parameters were reported. There was no remarkable change on plasma pharmacokinetics of 6beta-naltrexol after multiple intramuscular administrations.

Structure-activity relationships analysis of thienorphine and its derivatives / 药学学报

Thienorphine is a chemically-new opioid developed in Beijing Institute of Pharmacology and Toxicology. To elucidate the chemical basis for the unique pharmacological effects of thienorphine, 15 derivatives were synthesized according to combinatorial chemistry and the structure-activity relationships of these compounds were studied. It is demonstrated that thienorphine is a potent long-acting partial agonist. N-Cyclopropylmethyl is responsible for the antagonist effect of thienorphine. More importantly, thiophene at the end of side chain is most likely the pharmacophore accounts for the long-lasting effect of thienorphine. Change of the connection of thiophene and the side chain does not result in changes in the antinociceptive activity.

Detection of blood dissemination during the operation of lung cancer and its significance / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the possibility of dissemination of lung cancer cells through blood during the operation for lung cancer.</p><p><b>METHODS</b>The blood samples were taken from 52 patients with non-small cell lung cancer (NSCLC) and 5 patients with benign lung diseases at four different intervals during the operation. The transcription of carcinoembryonic antigen (CEA) messenger ribonucleic acid was assayed by means of nested reverse transcriptase polymerase chain reaction (RT-PCR). A549 (a human adenocarcinoma cell line) served as positive control. The sensitivity has been tested using quantificationally diluted A549 cells.</p><p><b>RESULTS</b>The CEA mRNA positive rates of all four time spots are as follows: 31% (16/52) at beginning of the operation (sample taken from peripheral vein), 54% (28/52) at ligating the pulmonary vein (peripheral vein), 54% (28/52) at ligating the pulmonary vein (pulmonary vein) and 54% (28/52) at 1 hour after ligating the pulmonary vein (peripheral vein). There is no relationship between the tumor identity and the positive rate of CEA mRNA. The positive rate of CEA mRNA is higher in patients with centrally located lung cancer than that in patients with peripherally located lung cancer, similar phenomenon is also found between patients with advanced lung cancer and the patients with early stage of lung cancer. No negative control samples was found to be positive for CEA mRNA, the sensitivity of our test was 1 x 10(-6).</p><p><b>CONCLUSIONS</b>The cancer cell dissemination during operation was demonstrated indirectly in our study, the time of pulmonary vein ligation (later or earlier) may affect the quantity of tumor cells released into circulation. Patients with lung cancer of central type and late TNM stage have more possibility of cancer cell dissemination during operation. More effective means may be needed to avoid the dissemination of cancer cells.</p>

Significance of microvascular density and vascular endothelial growth factor in breast cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the significance of vascular endothelial growth factor (VEGF) and microvascular density (MVD) expression in breast cancer.</p><p><b>METHODS</b>The expression of MVD and VEGF was studied in 81 patients with primary breast cancer by SP immunohistochemical technique.</p><p><b>RESULTS</b>There were 49 patients with high VEGF expression (60.5%) and 35 patients with high MVD expression (43.2%). There was significant correlation between VEGF or MVD expression and TNM stage, but not age, tumor size, ER expression or lymph node status. VEGF was significantly related with MVD expression. Univariate analysis showed that patients with low expression of VEGF and MVD had longer disease free survival (DFS) and overall survival (OS). Grouping univariate analysis showed that VEGF had significant correlation with the DFS of all grouped patients and the OS of patients with LN(+) or stage III lesions. MVD had significant correlation with the DFS and OS of LN(+) patients and the DFS of stage III lesion patients. Multivariate analysis showed that MVD was a risk predictor because of its positive statistic value, the higher expression, the shorter survival time of the patients.</p><p><b>CONCLUSION</b>Both VEGF and MVD are useful prognostic factors in breast cancer. MVD appears to be a strong and independent biologic marker for breast cancer prognosis.</p>

Comparison of the antagonistic effects of 6 beta-naltrexol and naltrexone against morphine analgesia / 药学学报

<p><b>AIM</b>To compare the antagonistic effects of 6 beta-naltrexol and naltrexone against morphine analgesia.</p><p><b>METHODS</b>The effects of 6 beta-naltrexol and naltrexone against morphine analgesia were observed in mouse heat radiant tail-flick assay and in mouse (55 +/- 1) degrees C hot plate test. The displacement of 6 beta-naltrexol and naltrexone on binding to CHO-mu receptor was observed by radioligand binding study.</p><p><b>RESULTS</b>6 beta-naltrexol antagonized morphine analgesia but the potency was (6.1 +/- 1.7)% that of naltrexone. The effective duration of 6 beta-naltrexol was 3-4 times that of naltrexone and the peak time of the response was about 0.5-1 h after s.c. equivalent efficacy dose (ED95) in two models. Like naltrexone, 6 beta-naltrexol was effective by oral administration and the potency ratio of p.o./s.c. was 1/3. As an antagonist to opioid receptor, the displacement of 6 beta-naltrexol was about 12.5% that of naltrexone, which was almost in agreement with the efficacies against morphine analgesia in mouse.</p><p><b>CONCLUSION</b>Compared with naltrexone, 6 beta-naltrexol was less potent but duration was longer.</p>