PURPOSE This study examined the expression and function of inward rectifier K(+) channels in cultured rat hepatic stellate cells (HSC). MATERIALS AND METHODS The expression of inward rectifier K(+) channels was measured using real-time RT-PCR, and electrophysiological properties were determined using the gramicidin-perforated patch-clamp technique. RESULTS The dominant inward rectifier K(+)...

Riluzole is the only FDA-approved drug to treat amyotrophic lateral sclerosis, but its long-term effects on motoneurons are unknown. Therefore, we treated primary mouse spinal cord cultures with 2 μM riluzole for 4-9 days and then used whole cell patch clamp to record the passive and active properties of both wild-type and SOD1(G93A) motoneurons. At this concentration, riluzole blocks >50% of t...

Slow ionic currents were measured in the rat omohyoid muscle with the three-microelectrode voltage-clamp technique. Sodium and delayed rectifier potassium currents were blocked pharmacologically. Under these conditions, depolarizing test pulses elicited an early outward current, followed by a transient slow inward current, followed in turn by a late outward current. The early outward current ap...

By means of an improved double sucrose gap technique the dependence of the slow inward current in small frog atrial trabeculae on the activation pattern was studied. Increasing the frequency of depolarizing voltage steps (pacing) the steady state slow inward current (TTX resistent and blocked by verapamil) was decreased. After a 300 s resting interval the slow inward current was increased but d...

Considerable interest has recently focused on the weaver mutation, which causes inward rectifier channel alterations leading to profound impairment of neuronal differentiation and to severe motor dysfunction in mice (Hess, 1996). The principal targets of mutation are cerebellar granule cells, most of which fail to differentiate and degenerate in a premigratory position (Rakic and Sidman, 1973a,...

Patch-clamp experiments were conducted to study the effects of basal lamina (basement membrane) of preovulatory chicken ovarian follicle on membrane currents in differentiated chicken granulosa cells in a homologous system. The membrane capacitance (measure of total membrane area) was smaller in cells cultured on intact basal lamina than that of control cells. The granulosa cells expressed outw...

The slow inward calcium currents were compared in rat and guinea pig heart using enzymatically dissociated, single ventricular cells. A single electrode voltage clamp was used, in which current and voltage were sampled separately using a time-sharing method. Spatial homogeneity of membrane potential during peak slow inward calcium current was assessed by measuring the potential with two microel...