Detail of "75558-90-6"

Reference

Entrapping of the spin label tempocholine into human erythrocytes by resealing after hyposmolar stress

Entrapping of the spin label tempocholine into human erythrocytes by resealing after hyposmolar stress. Comparison with hemolysis. The effects of some membrane-active substances. Lagercrantz, Carl; Larsson, Thomas; Tollsten, Lars; Prus, Karen (Dep. Med. Phys., Univ. Goeteborg, Goeteborg S-400 33, Swed.). Biochem. Pharmacol., 34(1), 31-8 (English) 1985. CODEN: BCPCA6. ISSN: 0006-2952. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Section cross-reference(s): 9 Human erythrocytes were subjected to a sudden hyposmolar stress by suspension in solns. of varying salt concns. in the presence of the spin label tempocholine [50669-92-6] iodide. The enlarged pores in the erythrocyte membranes produced by the influx of water, followed by stretching, allowed the passage of the spin label, so that a certain amt. of tempocholine was entrapped when the erythrocytes spontaneously resealed with closing of the pores. The excess of spin label in the external soln. was then reduced to a diamagnetic species by the addn. of ascorbic acid. The pos. charged tempocholine and the ascorbic acid did not penetrate properly resealed erythrocytes, so that the ESR signal from the entrapped spin label constituted a measure of the effective resealing of the pores and rifts in the membrane subsequent to hyposmolar stress. Some drug substances were found to influence the entrapping curves obtained when the amt. of entrapped spin label was plotted against the osmolarity. Chlorpromazine [50-53-3], trifluoperazine [117-89-5], nicardipine [55985-32-5], amperozide [75558-90-6], and haloperidol [52-86-8] gave rise to a dose-dependent decrease of the entrapping of tempocholine, esp. at low osmolarities. The exclusion of Ca2+ and Mg2+ ions from the solns. increased the action of chlorpromazine. The protective action against hemolysis brought about by a no. of membrane-active substances at low concns. had its counterpart in the entrapping curve obsd. with chlorpromazine at 0.1 mM. Apparently, the substances in this series exerted their action on the resealing process by interaction with the calmodulin system.

Antiarrhythmic effect of amperozide, a novel psychotropic compound with class III antiarrhythmic properties, on digoxin-induced arrhythmias in the guinea pig

Antiarrhythmic effect of amperozide, a novel psychotropic compound with class III antiarrhythmic properties, on digoxin-induced arrhythmias in the guinea pig. Hoeglund, Peter; Eriksson, Margareta; Christensson, Erik G. (Dep.Several substances are used for example 75558-90-6 and 20830-75-5 which are their cas registry numbers. Clin. Pharmacol., Univ. Hosp. Lund, Lund S-221 85, Swed.). J. Pharm. Pharmacol., 38(11), 861-3 (English) 1986. CODEN: JPPMAB. ISSN: 0022-3573. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) The antiarrhythmic activity of Amperozide (I) [75558-90-6] was compared with that of melperone, thioridazine, bretylium, and lignocaine. The drugs were given i.p. to anesthetized guinea-pigs, which 10 min later were given digoxin [20830-75-5] s.c. to induce arrhythmia. In a series of control expts. none of these compds. caused arrhythmia in combination with the vehicle or digoxin. The time to arrhythmia was significantly prolonged after treatment with amperozide, melperone, and bretylium compared with saline, but there were no differences between the treatments. Thus, these 3 drugs share class III antiarrhythmic properties. The digoxin concns. in plasma at death varied considerably within the groups and no statistical significance was found. .