leukotriene-b4 and dauricine

The effects of leukotrienes (LTs) and platelet activating factor (PAF) on DNA synthesis in bovine anterior cerebral arterial smooth muscle cells were studied. The results showed that LTB4, LTD4 and PAF were all stimulatory to the cells. The maximal rates of stimulation were 32%, 29% and 77%, respectively, for LTB4, LTD4 and PAF at 10(-7) mol/L. Both dauricine and anisodamine at concentrations of 10(-7) to 10(-4) mol/L exhibited strong inhibitory effects on LTs and PAF induced DNA synthesis.

Topics: Alkaloids; Animals; Benzylisoquinolines; Cattle; Cells, Cultured; Cerebral Arteries; DNA; Isoquinolines; Leukotriene B4; Muscle, Smooth, Vascular; Platelet Activating Factor; Platelet Aggregation Inhibitors; Solanaceous Alkaloids; SRS-A; Tetrahydroisoquinolines; Vasodilator Agents

The effects of dauricine (Dau), an isoquinoline alkaloid and anti-arrhythmic agent used in China recently, on the biosynthesis of metabolites of arachidonic acid in rat pleural neutrophils, comparing with dazoxiben, indomethacin and BW-755 c, were studied. The major products of metabolism by 5-lipoxygenase (5-LPO), measured by HPLC, were LTB4 and 5-HETE, whereas the major cyclooxygenase products measured by HPLC and RIA, were HHT and TXB2. The formation of all products by neutrophils was significantly depressed by Dau in a dose-dependent manner. The concentration of Dau required to obtain 50% inhibition (IC50) of formation of HHT, TXB2, LTB4 and 5-HETE was 25.3, 59.3, 31.8 and 59.5 mumol/L, respectively. These results indicate that the two major metabolic pathways of arachidonic acid in rat pleural neutrophils are inhibited by Dau.

Topics: Alkaloids; Animals; Arachidonic Acids; Benzylisoquinolines; Dose-Response Relationship, Drug; Fatty Acids, Unsaturated; Hydroxyeicosatetraenoic Acids; Isoquinolines; Leukotriene B4; Male; Neutrophils; Rats; Rats, Inbred Strains; Tetrahydroisoquinolines; Thromboxane B2