introduction: antibiotic supplements are regularly used in neuronal culture media to control contamination however, they can interfere with the neuronal excitability and affect electrophysiological properties. therefore, in this study, the effect of penicillin/streptomycin supplements on the spontaneous electrophysiological activity of hippocampal pyramidal neurons was examined. methods: electr...

background: ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. the mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. we aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex b...

The activity of the cardiac Na(+)/Ca(2+) exchanger (NCX1.1) undergoes continuous modulation during the contraction-relaxation cycle because of the accompanying changes in the electrochemical gradients for Na(+) and Ca(2+). In addition, NCX1.1 activity is also modulated via secondary, ionic regulatory mechanisms mediated by Na(+) and Ca(2+). In an effort to evaluate how ionic regulation influenc...

The effect of riluzole on Kv4.3 was examined using the whole-cell patch-clamp technique. Riluzole inhibited the peak amplitude of Kv4.3 in a reversible, concentration-dependent manner with an IC(50) of 115.6 microM. Under control conditions, a good fit for the inactivation of Kv4.3 currents to a double exponential function, with the time constants of the fast component (tau(f)) and the slow com...

1. The patch-clamp technique has been used to examine the action of the chemical phosphatase 2,3-butanedione monoxime (BDM) on ATP-sensitive K+ channels (KATP-channels) from mouse isolated pancreatic beta-cells in the absence of ATP and Mg2+. 2. BDM reversibly inhibited whole-cell KATP-currents with a concentration for half maximal inhibition (K(i)) of 15 +/- 1 mM and a Hill coefficient (n) of ...

Prolonged depolarization induces a slow inactivation process in some K+ channels. We have studied ionic and gating currents during long depolarizations in the mutant Shaker H4-Delta(6-46) K+ channel and in the nonconducting mutant (Shaker H4-Delta(6-46)-W434F). These channels lack the amino terminus that confers the fast (N-type) inactivation (Hoshi, T., W.N. Zagotta, and R.W. Aldrich. 1991. Ne...

Cellular and molecular events can be investigated using electrophysiological techniques. In particular, the patch-clamp method provides detailed information. In addition, the patch-clamp technique has become a powerful method for investigating the mechanisms underlying the effects of acupuncture. In this paper, recent researches on how acupuncture might modulate electrophysiological responses i...

The purpose of this research is to investigate the critical period of voltage-gated Na(+) channel development in hippocampal CA1 neurons. Changes of Na(+) currents in acutely isolated hippocampal CA1 neurons of rats at different ages (0-4 weeks after birth) were recorded using the whole-cell patch-clamp technique. The results indicated that the maximum current density of Na(+) channels was incr...

The kinetic transitions of proton-activated WT KcsA and the noninactivating E71A mutant were studied at the single-channel level in purified, liposome-reconstituted preparations. Single-channel currents were recorded using patch-clamp techniques under nonstationary and steady-state conditions. Maximum-likelihood analyses reveal that the key influence of acidic pH is to increase the frequency of...

embryonic stem cells are capable of differentiating to variety of cell tissues including cardiomyocytes. this developmental change is accompanied with a great deal of ion channel expression and functions. mouse stem cell derived cardiomyocytes were prepared and separated to yield isolated single cell suspension for cell current recording. in the present study some properties of the k + -current...