Inhibition of activation of nuclear factor kappaB is responsible for inhibition of inducible nitric oxide synthase expression by higenamine, an active component of aconite root.
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Effects of higenamine on nitric oxide (NO) production and inducible NO synthase (iNOS) mRNA expression (RAW 264.7 cells), on vascular reactivity in vitro and in vivo (rats), and on survival rates (mice) and serum nitrite/nitrate levels (rats) were investigated by using last lipopolysaccharide (LPS) plus interferon (IFN)-gamma. Higenamine concentration-dependently inhibited NO production and inducible NO synthase mRNA in RAW 264.7 cells, in which the IC(50) was 53 microM. Higenamine (10 mg/kg i.p.) administered 90 min before LPS (5 mg/kg i.v.) prevented not only LPS-induced hypotension but also pressor response to norepinephrine (1 microgram/kg) in rats. Incubation of thoracic aorta with LPS (300 ng/ml) for 8 h in vitro resulted in suppression of the vasoconstrictor effects to phenylephrine, which was prevented by coincubation with higenamine. The survival rate to endotoxin in mice was significantly (P <.01) increased by the presence of higenamine in the LPS-treated group up to 48 h. Serum nitrite/nitrate levels were significantly (P <.05) reduced by higenamine in LPS-treated rats. Finally, higenamine inhibited the activation of nuclear factor kappaB in RAW 264.7 cells due to LPS + IFN-gamma by mobility shift assays. Taken together, these data strongly suggest that higenamine inhibits iNOS expression by inhibiting nuclear factor kappaB activation by LPS + IFN-gamma, which may be beneficial in inflammatory diseases in which enhanced formation of NO is the main causative factor. Furthermore, due to positive inotropic action, higenamine may be more effective in a condition where myocardial contractility is likely to depress, such as in septic shock and/or endotoxin-induced inflammatory disorders. (+info)
Distribution of Aconitum alkaloids in body fluids and tissues in a suicidal case of aconite ingestion.
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A case involving a suicidal ingestion of Aconitum tubers is presented. A 40-year-old woman in Hokkaido, Japan ingested ground aconite and died of aconite intoxication about 4 h after ingestion. The Aconitum alkaloids were quantitated using gas chromatography-selected ion monitoring from extracts of the body fluids and organs. The blood and urine concentrations of jesaconitine, the main alkaloid of the aconite in this case, were 69.1 ng/mL and 237.8 ng/mL, respectively. Higher values of the alkaloid were demonstrated in the kidneys, the liver, and in the bile rather than other organs or serum, suggesting the alkaloids were eliminated by the liver and kidneys. In the gastrointestinal tract, the highest value of jesaconitine (471.3 ng/g) was in the ileal contents. These findings show that Aconitum alkaloids were found in the liver and kidneys in much higher concentrations than in serum and suggest that they were eliminated not only via urine but also in feces. Feces may be useful to detect Aconitum alkaloid if other biological samples are not available. (+info)
Vasorelaxing effect of mesaconitine, an alkaloid from Aconitum japonicum, on rat small gastric artery: possible involvement of endothelium-derived hyperpolarizing factor.
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Aconiti tuber, roots of aconite (Aconitum japonicum), has been used for centuries in Japan and China to increase peripheral body temperature. We previously reported that mesaconitine, an alkaloid from Aconitum japonicum, elicits endothelium-dependent and nitric oxide-mediated relaxation in isolated rat aorta. In the present study, we investigated the effect of mesaconitine on isolated rat small gastric arteries. Mesaconitine elicited a concentration-dependent (10, 30, 100 microM) vasorelaxation in isolated rat gastric artery precontracted with norepinephrine, which was resistant to N(omega)-nitro-L-arginine (L-NNA) (an inhibitor of nitric oxide synthase) and indomethacin (an inhibitor of cyclooxygenase). The L-NNA- and indomethacin-resistant relaxation by mesaconitine was mainly endothelium-dependent, inhibited by high K+ (30 mM), and inhibited by a combination of Ca2+-dependent K channel blockers, charybdotoxin and apamin. The relaxation by mesaconitine was proportional to the external Ca2+ concentration. These results suggest that mesaconitine elicits vasorelaxation of isolated rat small gastric artery mainly via release of endothelium-derived hyperpolarizing factor. (+info)
Hemsleyatine, a novel C19-diterpenoid alkaloid with 8-amino group from Aconitum hemsleyanum.
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The new compound hemsleyatine (1) was isolated along with four known C(19)-diterpenoid alkaloids: indaconitine (4), yunaconitine (5), chasmanine (6), and talatisamine (7) from the roots of Aconitum hemsleyanum PRITZ. Structures were established by spectral analysis, including tow dimeusional (2D) NMR spectroscopy and a chemical method. Hemsleyatine (1) is the first C(19)-diterpenoid alkaloid bearing the 8-amino group. In addition, the assignments of some (13)C signals for pseudaconine (3) were revised by comparison with those of hemsleyatine (1). (+info)
Norditerpenoid alkaloids from the processed tubers of Aconitum carmichaeli.
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Four new and five known norditerpenoid alkaloids were isolated from the processed tubers of Aconitum carmichaeli. The new alkaloids are 14-O-cinnamoylneoline (3), 14-O-anisoylneoline (4) 14-O-veratroylneoline (5), and lipo-14-O-anisoylbikhaconine (8). The known alkaloids are neoline (1), 14-O-acetylneoline (2), foresaconitine (6), crassicauline A (7), and lipohypaconitine (9). Alkaloids 2, 6, and 7 were isolated from this plant for the first time. The structures of the new alkaloids were established by spectroscopic and chemical methods. (+info)
MECHANISM OF ATRIAL FLUTTER AND FIBRILLATION INDUCED BY ACONITINE IN THE DOG, WITH OBSERVATIONS ON THE ROLE OF CHOLINEGIC FACTORS.
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The topical application of aconitine nitrate to the right atrial appendage in the "intact" anaesthetized dog produced atrial flutter. Premature systoles with fixed coupling preceded the development of flutter. In early stages of the arrhythmia, atrial rate was irregularly irregular. Also, the form of flutter beats was similar to that of preceding premature systoles. The fibrillatory activity of acetylcholine described by earlier workers has been confirmed. Transient atrial dissociation was seen after intravenous injection or topical application of acetylcholine. The occurrence of fibrillation in the left atrium after focal application of acetylcholine has been demonstrated, while the right atrial appendage containing the ectopic focus induced by aconitine continued to flutter. Aconitine produced slow-rate flutter in dogs treated with atropine or hemicholinium; this flutter was easily distinguishable from the sinus tachycardia produced by these drugs, by recording the electrocardiogram from a direct atrial lead from the area treated with aconitine, but not from limb lead II. The importance of these findings in the interpretation of the mechanism of atrial flutter and fibrillation is discussed. (+info)
THE EFFECT OF ACONITINE ON THE GIANT AXON OF THE SQUID.
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In the giant axon of Loligo pealii, "aconitine potent" Merck added to the bath (10(-7) to 1.25 x 10(-6) gm/ml) (a) had no effect on resting membrane potential, membrane resistance and rectification, membrane response to subthreshold currents, critical depolarization, or action potential, but (b) on repetitive stimulation produced oscillations of membrane potential after the spike, depolarization, and decrease of membrane resistance. The effect sums with successive action potentials; it increases with concentration of aconitine, time of exposure, and frequency of stimulation. When the oscillations are large enough and the membrane potential is 51.6 +/- SD 1.5 mv a burst of self-sustained activity begins; it usually lasts 20 to 70 sec. and at its end the membrane potential is 41.5 +/- SD 1.9 mv. Repolarization occurs with a time constant of 2.5 to 11.1 min. Substitution of choline for external sodium after a burst hyperpolarizes the membrane to -70 mv, and return to normal external sodium depolarizes again beyond the resting membrane potential. The effect of aconitine on the membrane is attributed to an increase of sodium and potassium or chloride conductances following the action potential. (+info)
Structure identification of five unknown dilipo-alkaloids extracted from processed tuber of Aconitum Carmiechaeli by electrospray ionization tandem mass spectrometry.
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The alkaloids in processed aconite tuber of Aconitum Carmiechaeli were studied, and five novel alkaloids in extract from processed aconite tuber were found. The first step involved the use of electrospray ionization mass spectrometry (ESI-MS), and then multi-stage tandem mass spectrometry (MSn) was used to provide structural information. Based on their MSn spectra, the structures of the five novel compounds were elucidated to be C3,C8-difatty acid esters of mesaconitine, aconitine and 10-hydroxyaconitine. (+info)