Zeiske, Wolfgang, Ilse Smets, Marcel Ameloot, Paul Steels, and Willy Van Driessche. Intracellular pH shifts in cultured kidney (A6) cells: effects on apical Na1 transport. Am. J. Physiol. 277 (Cell Physiol. 46): C469–C479, 1999.—We report, for the epithelial Na1 channel (ENaC) in A6 cells, the modulation by cell pH (pHc) of the transepithelial Na1 current (INa), the current through the individu...

BACKGROUND Dysregulation of voltage-gated cardiac Na(+) channels (NaV1.5) by inherited mutations, disease-linked remodeling, and drugs causes arrhythmias. The molecular mechanisms whereby the NaV1.5 voltage-sensing domains (VSDs) are perturbed to pathologically or therapeutically modulate Na(+) current (INa) have not been specified. Our aim was to correlate INa kinetics with conformational chan...

We report evidence for a contribution of tetrodotoxin-resistant sodium current (TTX-R INa) to prostaglandin E2 (PGE2)-induced hyperalgesia. Behavioral experiments were performed in rats chronically implanted with spinal cannulae. The study employed intrathecal administration of oligodeoxynucleotide (ODN) antisense to the recently cloned channel underlying TTX-R INa (PN3/SNS). The nociceptive fl...

The properties of the Na+ current present in thalamocortical neurons of the dorsal lateral geniculate nucleus were investigated in dissociated neonate rat and cat neurons and in neurons from slices of neonate and adult rats using patch and sharp electrode recordings. The steady-state activation and inactivation of the transient Na+ current (INa) was well fitted with a Boltzmann curve (voltage o...

BACKGROUND As the rapid growth of the elderly population and the increased prevalence of Alezheimer's Disease and related disorders, there is an increasing need for effective cognitive screening. The Mini Mental State Examination (MMSE) is the most frequently used screening test of cognitive impairment because of its convenience. The Montreal Cognitive Assessment-Indonesian Version (MoCA-INA) h...

The apolar azide of 5-iodonaphthalene-1-azide (Ina) partitions into the lipid bilayer of biological membranes. Upon photolysis at 314 nm, it is rapidly converted into the reactive nitrene, which efficiently attaches covalently to lipid-embedded domains of proteins and, to a lesser extent, to membrane phospholipids. Above 370 nm, Ina absorption is negligible and photolysis at these wavelengths d...

In the mammalian heart fibroblasts have important functional roles in both healthy conditions and diseased states. During pathophysiological challenges, a closely related myofibroblast cell population emerges, and can have distinct, significant roles. Recently, it has been reported that human atrial myofibroblasts can express a Na(+) current, INa. Some of the biophysical properties and molecula...

Objective: Catecholamines that accompany acute physiological stress are also involved in mediating the development of hypertrophy and failure. However, the cellular mechanisms involved in catecholamine-induced cardiac hypertrophy, particularly Ca + handling, are largely unknown. We therefore investigated the effects of cardiac hypertrophy, produced by isoprenaline, on INa/Ca and sarcoplasmic re...

1 The antiarrhythmic drug mexiletine (Mex) is also used against myotonia. Searching for a more efficient drug, a new compound (Me5) was synthesized substituting the methyl group on the chiral carbon atom of Mex by an isopropyl group. Effects of Me5 on Na+ channels were compared to those of Mex in rat skeletal muscle fibres using the cell-attached patch clamp method. 2 Me5 (10 microM) reduced th...