OBJECTIVETo establish a method for screening cysteinyl leukotriene receptor 2 (CysLT(2)) antagonists and to preliminarily screen a series of synthetic compounds.

METHODSRat glioma cell line (C6 cells) highly expressing CysLT(2) receptor was used. Intracellular calcium concentration was measured after stimulation with the agonist LTD(4),which was used to screen compounds with antagonist activity for CysLT(2) receptor. Bay u9773, a CysLT1/CysLT(2) receptor non-selective antagonist, and AP-100984, a CysLT(2) receptor antagonist, were used as control.

RESULTPT-PCR showed a higher expression of CysLT(2) receptor in C6 cells. LTD(4) at 1 mumol/L significantly increased intracellular calcium in C6 cells; the maximal effect was about 37.5% of ATP, a positive stimulus.LTD(4)-induced increase of intracellular calcium was blocked by CysLT(2) receptor antagonists, but not by CysLT(1) receptor antagonists. Among the synthetic compounds, D(XW-)1,2,13,23,29 and 30 inhibited LTD(4)-induced increase of intracellular calcium.

CONCLUSIONLTD(4)-induced change in intracellular calcium in C6 cells can be used as a screening method for CysLT(2) receptor antagonists. The compounds, D(XW-)1,2,13,23,29 and 30, possess antagonist activity for CysLT(2) receptor.

Animals ; Brain Neoplasms ; pathology ; Cell Line, Tumor ; Drug Evaluation, Preclinical ; methods ; Glioma ; pathology ; Leukotriene Antagonists ; isolation & purification ; Leukotriene D4 ; metabolism ; pharmacology ; Rats ; Receptors, Leukotriene ; chemistry

OBJECTIVETo investigate the effects of CysLT receptor agonist leukotriene D4(LTD4) and antagonists on activation of microglia BV2 cells.

METHODSThe expression of CysLT1 and CysLT2 protein was determined by Western blotting and immunostaining in microglia BV2 cells. BV2 cells were pretreated with or without CysLT1 receptor selective antagonist montelukast, CysLT2 receptor selective antagonist HAMI 3379, or CysLT1/CysLT2 receptor dual antagonist BAY u9773 for 30 min, then the cells were treated with LTD4 for 24 h. Cell viability was detected by MTT reduction assay. Phagocytosis and mRNA expression of IL-6 were determined by fluorescent bead tracking and RT-PCR, respectively.

RESULTSIn BV2 cells, LTD4 did not affect proliferation but significantly enhanced phagocytosis and increased IL-6 mRNA expression in a concentration-dependent manner. LTD4 at 100 nmol/L induced a 1.4-fold increase of phagocytic index and a 2-fold up-regulation of IL-6 mRNA expression (P<0.01). HAMI 3379 and BAY u9773 (100 nmol/L) further increased LTD4-induced phagocytosis; BAY u9773 and montelukast decreased LTD4-induced IL-6 mRNA expression, while HAMI 3379 had no effect on that.

CONCLUSIONLTD4 activates BV2 cells in vitro and enhances IL-6 mRNA expression mediated by CysLT1 receptor, LTD4 induces phagocytosis which might be negatively regulated by CysLT2 receptor in BV2 cells.

Acetates ; pharmacology ; Cell Line ; Cell Proliferation ; Cyclohexanecarboxylic Acids ; pharmacology ; Humans ; Interleukin-6 ; metabolism ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Microglia ; cytology ; metabolism ; Phagocytosis ; Phthalic Acids ; pharmacology ; Quinolines ; pharmacology ; Receptors, Leukotriene ; metabolism ; SRS-A ; analogs & derivatives ; pharmacology

OBJECTIVETo determine the effect of cysteinyl receptor agonist leukotriene D(4) (LTD(4)) and its antagonists on rat primary neurons.

METHODSIn the primarily cultured rat cortical neurons, the neuron injury was evaluated by measuring intracellular calcium, 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyl tetrazolium bromide (MTT) reduction, and propidium iodide (PI) and Hoechst 33258 staining. The in vitro ischemic injury was induced by oxygen-glucose deprivation (OGD) for 1.5 h and reperfusion for 24 h.

RESULTLTD(4) (0.01-1 micromol/L) did not induce the elevation of intracellular calcium, neuron viability changes and neuron death. OGD-induced injury was not significantly ameliorated by the CysLT(1) receptor antagonists, pranlukast (0.2-10 micromol/L) and montelukast (0.2-10 micromol/L), as well as by the CysLT(1)/CysLT(2) receptor non-selective antagonist, BAY u9773 (0.02-1 micromol/L).

CONCLUSIONNeither agonist nor antagonists of cysteinyl receptors have the effects on the viability and ischemic-like injury in rat primary neurons.

Acetates ; pharmacology ; Animals ; Animals, Newborn ; Calcium ; metabolism ; Cell Hypoxia ; Cell Survival ; drug effects ; Cells, Cultured ; Cerebral Cortex ; cytology ; Chromones ; pharmacology ; Glucose ; pharmacology ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Neurons ; cytology ; drug effects ; metabolism ; Quinolines ; pharmacology ; Rats ; Receptors, Leukotriene ; agonists

Acetates ; adverse effects ; pharmacology ; therapeutic use ; Animals ; Asthma ; drug therapy ; Humans ; Leukotriene Antagonists ; pharmacology ; Quinolines ; adverse effects ; pharmacology ; therapeutic use ; Receptors, Leukotriene ; drug effects

OBJECTIVETo investigate the role of cysteinyl leukotriene (CysLT) receptors in the differentiation of rat glioma C6 cells.

METHODSRat glioma C6 cells were treated with the agonist LTD(4), the CysLT(1) receptor antagonist montelukast and the differentiation inducer forskolin. Cell morphology and GFAP protein expression were determined after treatments.

RESULTForskolin (10 μmol/L) induced morphological changes and GFAP protein expression (cell differentiation) in C6 cells, but LTD(4) (0.1-100 nmol/L) did not induce these changes. Montelukast (1 μmol/L) alone did not affect C6 cell differentiation, while it induced the differentiation when combined with the LTD(4) (100 nmol/L).

CONCLUSIONThe CysLT(2) receptor may modulate the differentiation of rat glioma C6 cells.

Acetates ; pharmacology ; Animals ; Cell Differentiation ; drug effects ; Cell Line, Tumor ; Colforsin ; pharmacology ; Cysteine ; Glioma ; metabolism ; pathology ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Leukotrienes ; Quinolines ; pharmacology ; Rats ; Receptors, Leukotriene ; agonists

OBJECTIVETo determine whether cysteinyl leukotriene receptor agonist LTD(4) and cysteinyl leukotriene receptor 1 (CysLT(1)) antagonist pranlukast affect the differentiation of human neuroblastoma SK-N-SH cells.

METHODSSK-N-SH cell morphological changes induced by LTD(4), pranlukast and LTD(4) + pranlukast were observed with retinoid acid (RA) as the positive control. The expressions of CysLT(1) and CysLT(2) receptors were detected by immunoblotting analysis, and the expression of microtubule-associated protein-2 (MAP-2), a neuron marker, was detected by fluorescent immunostaining.

RESULTThe immunoblotting results showed that SK-N-SH cells expressed CysLT(1) receptor moderately, and CysLT(2) receptor highly. The morphological results showed that RA, pranlukast and LTD(4) + pranlukast induced the compaction of the cell bodies and the outgrowth of neurites, while LTD(4) had no significant effect. The immunostaining results showed that MAP-2 was distributed in the cell bodies in control or pranlukast-treated cells; it was distributed in cell bodies and neuritis in RA-treated cells. Pranlukast increased the numbers of MAP-2-positive cells.

CONCLUSIONThe CysLT(1)receptor antagonist pranlukast modulates the differentiation of SK-N-SH cells.

Cell Differentiation ; drug effects ; Cell Line, Tumor ; Chromones ; pharmacology ; Humans ; Immunoblotting ; Immunohistochemistry ; Leukotriene Antagonists ; pharmacology ; Leukotriene D4 ; pharmacology ; Membrane Proteins ; metabolism ; Microtubule-Associated Proteins ; metabolism ; Neuroblastoma ; metabolism ; pathology ; Receptors, Leukotriene ; metabolism

OBJECTIVE: To investigate the changes of leukotriene D4 (LTD4) in nasal discharge and plasma of patients with persistent allergic rhinitis (AR) and the effects of antihistamine. METHOD: The investigation was a prospective, randomized controlled trial. Forty AR patients (group C) were divided randomly into two subgroup. One group received oral antihistamine 10 mg everyday for one week (group CA) and another group received no loratadine tablets 10 mg everyday for one week (group CB). Fifteen age matched healthy (group D) people were enrolled as control. The level of LTD4 and interleukin-5 (IL-5) in both nasal discharge and plasma by using enzyme linked immunosorbent assay (ELISA) and enzyme immunoassay (EIA), cell counts and cell differentials in nasal discharge, were measured before and after three month. The clinical symptom and life quality scores of group C were also investigated. RESULT: The concentrations of LTD4 in nasal discharge [(794 +/- 305) pg] and plasma [(5219 +/- those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P 1185) ng/L] in group C were significantly higher than those in group D [(347 +/- 169) pg, (2283 +/- 489) ng/L, all P < 0.05]. The level of LTD4 in nasal discharge was positively correlated with the percentage of neutrophil (r = 0.453, P < 0.05) and IL-5 (r = 0.364, P < 0.05). The pre- and post-therapy concentrations of nasal discharge and plasma in group CA were (812 +/- 1592) pg, (657 +/- 495) pg and (5422 +/- 935) ng/L, (4589 +/- 1057) ng/L respectively; While in group CB the concentrations were (776 +/- 227) pg, (860 +/- 194) pg and (5074 +/- 1850) ng/L, (6063 +/- 450) ng/L, respectively. There were no significant difference either in the level of LTD4 in nasal discharge or in plasma in both groups (all P > 0.05). CONCLUSION The results suggested that LTD4 was involved in airway inflammation in AR. Antihistamine was not effective enough in decreasing the levels of LTD4 in both nasal discharge and plasma of AR patients.
Adult ; Anti-Allergic Agents ; pharmacology ; Bodily Secretions ; chemistry ; Female ; Histamine H1 Antagonists ; pharmacology ; Humans ; Leukotriene Antagonists ; therapeutic use ; Leukotriene D4 ; analysis ; blood ; metabolism ; Male ; Middle Aged ; Plasma ; chemistry ; Prospective Studies ; Rhinitis, Allergic, Perennial ; blood ; drug therapy ; metabolism

OBJECTIVETo observe the inhibitory effect of mizolastine on substance P(SP)-induced production of leukotriene B(4) (LTB(4)) and interleukin 5 (IL-5) in mouse skin.

METHODSMice were fed with different doses of mizolastine or other control drugs, 30 min after administration animals were injected intradermally with SP on the back. The treated skin samples were taken and competitive enzyme-link immunoassay (ELISA) method was applied to detect LTB (4) and IL-5 in the skin samples.

RESULTThe LTB(4) and IL-5 levels in 10 mg/kg mizolastine group were (1.23 +/-0.29)pg/ml and (34.28 +/-11.00)pg/ml, respectively, which were lower than those in saline control group [(5.52+/-1.88)pg/ml and (179.62 +/-46.25)pg/ml respectively] or loratadine group [(3.89+/-1.27)pg/ml and (127.74 +/-43.27)pg/ml respectively]. No significant difference was found between 10 mg/kg mizolastine group and dexamethasone group (P=0.161 and P=0.508).

CONCLUSIONMizolastine might inhibit the production of LTB(4) and IL-5 induced by substance P in mouse skin, suggesting that anti-inflammatory effect and the blockade of histamine H1 receptors might be involved in its anti-pruritic mechanisms.

Animals ; Benzimidazoles ; pharmacology ; Female ; Histamine H1 Antagonists ; pharmacology ; Interleukin-5 ; biosynthesis ; Leukotriene B4 ; biosynthesis ; Male ; Mice ; Mice, Inbred BALB C ; Skin ; metabolism ; Substance P ; antagonists & inhibitors

OBJECTIVE: : To investigate the effects of cysteinyl leukotrienes receptor (CysLTR) antagonists on global cerebral ischemia/reperfusion (CI/R) injury in gerbils, and to explore its mechanism. METHODS: : Totally 40 gerbils weighting 45-65 g were randomized into sham, saline, Pranlukast and HAMI 3379 groups with 10 animals in each. The CI/R model was established in gerbils by bilateral common carotid occlusion for 10 min followed by reperfusion. After ischemia, the CysLTR antagonists Pranlukast (0.1 mg/kg) and HAMI 3379 (0.1 mg/kg) were injected intraperitoneally for 5 consecutive days in the last two groups,while the former two groups were injected with saline only (10 mL/kg). After 24 h or 14 d reperfusion, neurological deficit score was evaluated and the behavioral dysfunction was assessed, respectively. And 14 d after reperfusion, the neuron morphology of cerebral cortex was observed in brain sections stained with Cresyl violet. In addition, the Iba-1 (microgila) and GFAP (astrocyte) positive cells in cerebral cortex were observed by using immunohistochemitry method. RESULTS: : CI/R models were successfully established in 21 out of 30 gerbils with 7 in saline group, 6 in Pranlukast group, and 8 in HAMI 3379 group. Compared with saline group, Pranlukast and HAMI 3379 significantly attenuated neurological deficits, improved the behavioral function 24 h after reperfusion(all <0.01); Pranlukast and HAMI 3379 also significantly improved the behavioral function 14 days after reperfusion(<0.05 or <0.01). Compared with saline group, the neurological symptom scores in Pranlukast and HAMI 3379 groups presented a trend of amelioration 14 d after reperfusion, but it was not significant(>0.05). In addition, Pranlukast and HAMI 3379 also inhibited the neuron loss and injury, suppressed microgila and astrocyte activation 14 d after reperfusion(all <0.01). CONCLUSIONS : CysLTR antagonists Pranlukast and HAMI 3379 have long-term neuroprotective effect on chronic brain injury induced by global cerebral ischemia/reperfusion in gerbils.
Animals ; Behavior, Animal ; drug effects ; Brain Injury, Chronic ; drug therapy ; Brain Ischemia ; Gerbillinae ; Leukotriene Antagonists ; pharmacology ; therapeutic use ; Neuroprotective Agents ; pharmacology ; therapeutic use ; Random Allocation ; Receptors, Leukotriene ; metabolism ; Reperfusion Injury ; drug therapy

OBJECTIVETo study the curative effect of leukotriene receptor antagonist on cough variant asthma (CVA).

METHODSSixty-four CVA patients received treatment with bricany and montelukas and 68 control patients had bricany treatment for 4 weeks. The recurrence rate was observed in the two groups during the follow-up for 6 months.

RESULTSThe remission time of two groups were 2.5-/+3.6 and 5.3-/+3.8 days in acute phase, respectively, showing a significant difference between them (P<0.05). The recurrence rate of the two groups within 6 months were 20.09% and 40.87%, respectively, showing also significantly differences (P<0.05).

CONCLUSIONLeukotriene receptor antagonist and bricany can effectively control CVA and significantly lower the short-term recurrence rate of CVA.

Adult ; Asthma ; complications ; drug therapy ; Case-Control Studies ; Cough ; complications ; drug therapy ; Female ; Follow-Up Studies ; Humans ; Leukotriene Antagonists ; adverse effects ; pharmacology ; therapeutic use ; Male ; Receptors, Leukotriene ; metabolism ; Recurrence