Rumpal, Nidhi and Gregory A. Lnenicka. Ca clearance at growth cones produced by crayfish motor axons in an explant culture. J Neurophysiol 89: 3225–3234, 2003; 10.1152/jn.00952.2002. Intracellular free Ca concentration ([Ca ]i) plays an important role in the regulation of growth cone (GC) motility; however, the mechanisms responsible for clearing Ca from GCs have not been examined. We studied t...

Values for ionized [Ca] in squid axons were obtained by measuring the light emission from a 0.1-mul drop of aequorin confined to a plastic dialysis tube of 140-mum diameter located axially. Ionized Ca had a mean value of 20 x 10(-9) M as judged by the subsequent introduction of CaEGTA/EGTA buffer (ratio ca. 0.1) into the axoplasm, and light measurement on a second aequorin drop. Ionized Ca in a...

Dog erythrocytes (RBC) have a system for passive Ca and Na movements that resembles the Ca-Na exchanger first described in cardiac muscle. Amrinone, a new cardiotonic drug active in humans with congestive heart failure, is shown to stimulate net Ca uptake by dog RBC. Amrinone's action is on Ca influx rather than efflux. The influence of Amrinone on Ca uptake is enhanced when the cells are place...

We measured [Ca]i and [Na ]i in isolated transgenic (TG) mouse myocytes overexpressing the Na -Ca exchanger and in wild-type (WT) myocytes. In TG myocytes, the peak systolic level and amplitude of electrically stimulated (ES) [Ca]i transients (0.25 Hz) were not significantly different from those in WT myocytes, but the time to peak [Ca]i was significantly prolonged. The decline of ES [Ca]i tran...

A high cytoplasmic Na concentration may contribute to Nmethyl-D-aspartate (NMDA)-induced excitotoxicity by promoting Ca influx via reverse operation of the Na/Ca exchanger (NaCaX), but may simultaneously decrease the electrochemical Ca driving force by depolarizing the plasma membrane (PM). Digital fluorescence microscopy was used to compare the effects of Na versus ions that do not support the...

Preservation of water quality, particularly in areas with inadequate water resources is considered as one of the principles of planning in integrated water management. In Kuhdasht, a region at the west of Iran, groundwater and spring water resources are the major contributors of drinking and irrigation water supply. The aim of this study was to determine the suitability and mapping of springs a...

Intracellular ATP supply and ion homeostasis determine neuronal survival and degeneration after ischemic stroke. The present study provides a systematic investigation in organotypic hippocampal slice cultures of the influence of experimental ischemia, induced by oxygen-glucose-deprivation (OGD). The pathways controlling intracellular Na(+) and Ca(2+) concentration ([Na(+)](i) and [Ca(2+)](i)) a...

KB130015 [KB; 2-methyl-3-(3,5-diiodo-4-carboxymethoxybenzyl)benzofuran] is a novel amiodarone derivative designed to retain the antiarrhythmic effects without the side effects. Unlike amiodarone, KB slows Na(+) current inactivation and could, via an increase in [Na(+)](i), potentially lead to Ca(2+) overload. Therefore, we studied the effects of KB on Na(+) and Ca(2+) handling in single pig ven...