BACKGROUND Pinacidil is known to augment a time-independent outward current in cardiac tissues by activating the ATP-regulated potassium channels. Activation of this current, IK-ATP, is thought to be responsible for increased potassium permeability in ischemia. The contribution of IK-ATP activation to arrhythmogenesis and the role of activation of this current in suppression of arrhythmias are ...

BACKGROUND Thallous chloride (201Tl) and hexakis(2-methoxyisobutyl isonitrile) technetium (I) (99mTc-SESTAMIBI) are myocardial perfusion imaging agents with biological properties that also reflect tissue viability. Initial myocellular uptake rates of 201Tl reflect activity of Na,K-ATPase, whereas those of 99mTc-SESTAMIBI reflect mean plasma membrane potential. METHODS AND RESULTS To better un...

Mechanosensitive ion channels have been described in many types of cells. These channels are believed to transduce pressure signals into intracellular biochemical and physiological events. In this study, the patch-clamp technique was used to idendfy and characterize a mechanosensitive ion channel in rat atrial cells. In cell-attached patches, negative pressure in the pipette activated an ion ch...

In pancreatic beta-cells, glucose metabolism signals insulin secretion by altering the cellular array of messenger molecules. ATP is particularly important, given its role in regulating cation channel activity, exocytosis, and events dependent upon its hydrolysis. Uncoupling protein (UCP)-2 is proposed to catalyze a mitochondrial inner-membrane H(+) leak that bypasses ATP synthase, thereby redu...

AIM To investigate the effect of Hemp seed soft capsule (HSCC) on colonic ion transport and its related mechanisms in constipation rats. METHODS Sprague-Dawley male rats were randomly divided into three groups: normal group, constipation group and HSSC group. Rats in the constipation and HSSC groups were administrated loperamide 3 mg/kg per day orally for 12 d to induce the constipation model...

Ischemic preconditioning, a phenomenon in which brief episodes of ischemia and reperfusion paradoxically protect the heart against subsequent lethal ischemia,1 has been conceptually divided into triggers and mediators/effectors.2,3 The trigger, which acts before the index ischemia, is followed by the protection of mediators/effectors during the lethal ischemia. Known triggers include activation...

Previous investigations have demonstrated that compounds capable of blocking presynaptic potassium channels can stimulate neurotransmitter release at both peripheral and central synapses. This study examined the in vitro effects of the “classical” potassium channel blockers 4-aminopyridine (4-AP) and tetraethylammonium (TEA) on the spontaneous basal release of [H]5-hydroxytryptamine ([H]5-HT) f...