We tried to establish the halothane-anesthetized microminipigs as an alternative animal model for non-clinical toxicity and/or safety pharmacology studies. In order to characterize the halothane-anesthetized microminipigs, we firstly clarified the effects of halothane anesthesia on their cardiovascular system (n = 5). Then, we examined the cardiovascular effects of dl-sotalol in doses of 0.
View Article and Find Full Text PDFBackground: In order to begin to precisely clarify the impact of renal denervation on the blood pressure, atrial fibrillation and ventricular tachyarrhythmias, in addition to proarrhythmic potential, its cardiovascular effects were assessed by using the chronic complete atrioventricular block dogs.
Methods and results: Cardiohemodynamic and electrophysiological effects, together with neurohumoral factors and/or electrolytes, were assessed before and 4 weeks after either renal denervation (n=5) or amiodarone treatment (n=6). Amiodarone hydrochloride was given orally to the animals every day in a dose of 200 mg/day for the first 7 days followed by 100 mg/day for the following 21 days.
Although acute treatment of pentamidine does not directly modify any ionic channel function in the heart at clinically relevant concentrations, its continuous exposure can prolong QT interval. Recent in vitro studies have indicated that hERG trafficking inhibition may play an important role in the onset of pentamidine-induced long QT syndrome. In this study, we examined acute in vivo electropharmacological effects of pentamidine using the halothane-anesthetized canine model (n = 5).
View Article and Find Full Text PDFWe report here that lysocellin, a polyether antibiotic from a streptomycete, induces G1 phase arrest in human osteosarcoma MG63 cells. Lysocellin up-regulates p21WAF1/Cip1 and down-regulates cyclin D1 at the mRNA level. In addition, cyclin D1 is down-regulated by the proteasome-dependent signal pathway in MG63 cells.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
October 2005
The solvolysis reaction of (4,5)-anti-4-aryl-5-tosyloxy-2(E)-hexenoates 4a-k gave (4,5)-anti-4-aryl-5-hydroxy-2(E)-hexenoates 2a-k and (4,5)-anti-5-aryl-4-hydroxy-2(E)-hexenoates 5a-k along with the complete inversion. This 1,2-aryl migration was induced by treatment with heating in water-saturated nitromethane. On the basis of the substituent effect on the aromatic ring, this 1,2-aryl migration is thought to proceed via the sigma-bridged phenonium ion.
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