Detail of "8051-02-3"

Reference

Potassium and veratrine-stimulated L-[3H]cysteine sulfinate and L-[3H]glutamate release from rat brain slices

Potassium and veratrine-stimulated L-[3H]cysteine sulfinate and L-[3H]glutamate release from rat brain slices. Recasens, M.; Fagni, L.; Baudry, M.; Lynch, G. (Dep. Psychobiol., Univ. California, Irvine, CA 92717, USA). Neurochem. Int., 6(3), 325-32 (English) 1984. CODEN: NEUIDS. ISSN: 0197-0186. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) The release of the 3H-labeled ligands L-cysteine sulfinic acid [1115-65-7], L-glutamic acid [56-86-0], and GABA [56-12-2] from preloaded slices of various rat brain regions in response to either 30 mM K+ or veratrine [8051-02-3] was investigated. All 3 amino acids were released by both depolarizing agents, which did not produce any changes in the spontaneous efflux of [3H]lysine. The K+-stimulated cysteine sulfinate release from superfused slices was partly Ca2+-dependent in the subiculum, and mainly Ca2+-independent in the hippocampus, whereas the K+-elicited glutamate release was partly Ca2+-dependent in both regions. The veratrine-induced release of both cysteine sulfinate and glutamate was blocked by verapamil in a dose-dependent way, although a small verapamil concn.-independent release remained. The release pattern of both amino acids was heterogeneous, but roughly correlated among brain regions, except in the subiculum and hypothalamus. These findings demonstrate the releasability of both substances from various brain regions and suggest that those releases occur from different pools, being probably mainly of neuronal origin. They give further evidence that cysteine sulfinate as well as glutamate may serve a neurotransmitter role in the central nervous system.

Sodium influx-induced decrease of sodium-potassium ATPase activity in rat brain slices: role of calcium

Sodium influx-induced decrease of sodium-potassium ATPase activity in rat brain slices: role of calcium. Matsuda, Toshio; Shimizu, Isao; Baba, Akemichi (Fac. Pharm. Sci., Osaka Univ., Suita 565, Japan). Eur. J. Pharmacol., 204(3), 257-63 (English) 1991. CODEN: EJPHAZ. ISSN: 0014-2999. DOCUMENT TYPE: Journal CA Section: 13 (Mammalian Biochemistry) Treatment of rat brain slices with veratrine and monensin decreased (Na+ + K+)-ATPase activity in the membranes in a dose-dependent manner. The effect of monensin, like that of veratrine, was accompanied by a decrease of maximal binding sites for ouabain. The inhibitory effect of monensin on the enzyme activity was dependent on external Ca2+ at low concns., but not at a high concn. 7440-70-2 and 8051-02-3 are cas registry numbers of chemicals which are used as reagents here. The decreased enzyme activity induced by monensin was restored by subsequent incubation of the slices in a Ca2+-free medium contg. 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester (BAPTA-AM), a chelator of intracellular Ca2+. The effect of monensin at a low concn. on enzyme activity was antagonized by amiloride (1 mM), bepridil (5 mM), quinacrine (30 mM) or verapamil (30 mM), but not by nifedipine (1 mM) or w-conotoxin (1 mM). Furthermore, the inhibitory effect of monensin at a high concn. under Ca2+-free conditions was blocked by BAPTA-AM (30 mM) and by bepridil (100 mM) or diazepam (500 mM), inhibitors of mitochondrial Na+-Ca2+ exchange. Inhibitors of calmodulin, protein kinase C, phospholipase A2 and calpain did not affect the monensin-induced decrease of enzyme activity. Dithiothreitol (10 mM) blocked the effect of monensin on enzyme activity but did not affect the ionophore-induced influx of Ca2+ in the slices. .