[Effects of donepezil on the delayed rectifier-like potassium current in pyramidal neurons of rat hippocampus and neocortex].

Aim: To investigat the effects of donepezil on delayed rectifier-like potassium currents (IK) in rat hippocampus and neocortex.

Methods: Whole cell configuration of the patch-clamp techniques were used to characterize IK in acutely isolated rat hippocampal and neocortical pyramidal neurons.

Results: The slowly inactivating outward currents (IK) were recorded in all cells under investigation.

[Effects of chronic exposure to beta-amyloid-peptide25-35 on the mRNA expressions of voltage-gated outward potassium channel subunits in cultured rat hippocampal neurons].

Aim: To investigate mRNA expression changes of voltage-gated outward potassium channel subtypes in cultured rat hippocampal neurons after chronic exposure to beta-amyloid-petitde25-35 (beta-AP25-35).

Methods: mRNA expression was detected by RT-PCR, comparative expression levels were determined by imaging densitometer.

Results: Delayed rectifying (Kv2.

KCNQ1 gain-of-function mutation in familial atrial fibrillation.

Atrial fibrillation (AF) is a common cardiac arrhythmia whose molecular etiology is poorly understood. We studied a family with hereditary persistent AF and identified the causative mutation (S140G) in the KCNQ1 (KvLQT1) gene on chromosome 11p15.5.

Galantamine blocks delayed rectifier, but not transient outward potassium current in rat dissociated hippocampal pyramidal neurons.

Galantamine is an acetylcholinesterase inhibitor in Alzheimer's disease therapy. In the present study, we investigated the effects of galantamine on delayed rectifier potassium current (I(K(DR))) and transient outward potassium current (I(K(A))) in acutely dissociated rat hippocampal pyramidal neurons by using whole-cell patch clamp technique. I(K(DR)) was inhibited by galantamine in a concentration-dependent manner, while I(K(A)) remained unaffected.

Altered gene expression of Na+/Ca2+ exchanger isoforms NCX1, NCX2 and NCX3 in chronic ischemic rat brain.

To investigate the effect of chronic global cerebral ischemia on gene expression of Na(+)/Ca(2+) exchanger isoforms NCX1, NCX2 and NCX3 in rat brain. Chronic global cerebral ischemia was induced by bilateral common carotid artery ligation (BCAL) in rats for 1 week, 2 weeks and 4 weeks, respectively. Morris water maze was applied to demonstrate the credibility of BCAL models.

Amiloride and KB-R7943 in outward Na+ /Ca2+ exchange current in guinea pig ventricular myocytes.

The reverse mode of Na+/Ca2+ exchange represents an important pathway in inducing Ca2+ overload during ischemia and reperfusion. The inhibitory effects of amiloride and KB-R7943 on Na+/Ca2+ exchange current (INa/Ca) were investigated in guinea pig ventricular myocytes. Whole-cell patch clamp techniques were used under bidirectional ionic conditions and 25 mM of Na+ in pipette solution.

[Voltage-gated potassium channels and human neurological diseases].

Voltage-gated potassium channels (Kv) is the largest, most complex in potassium channel superfamily. It can be divided into Kv alpha subunit and auxiliary two groups. The roles of some Kv channels types, e.

mRNA expression alterations of inward rectifier potassium channels in rat brain with cholinergic impairment.

Potassium channel dysfunction has been indicated in Alzheimer's disease. In the present study, spatial memory, the activity of cortical acetylcholinesterase (AChE) and the expressions of inward rectifier potassium channels (Kir) were measured after ibotenic acid lesions of nucleus basalis magnocellularis (nbm) in rats. Expressions of Kir (Kir2.