was readily constructed by simple modification of a common FID hydrocarbon monitor, with addition of a commercially available valve oven, switching valve, and timer. This system, except for the adjusted response time, had virtually the same operating specifications as the original hydrocarbon analyzer. Short-term studies indicated the system was practical, reliable, and accurate. Air-monitoring...

Potassium Channels To the Editor: We read with interest the publication by Lee et al1 describing the potential mechanisms and effects of intracoronary conjugated estrogens on coronary vasomotion and myocardial ischemia in patients undergoing percutaneous coronary angioplasty. We were surprised at the very high bolus dose of intracoronary Premarin (Wyeth-Ayerst) given—5 mg into the left coronary...

A preparation of dissociated Drosophila ommatidia is described that allows single-channel and whole-cell patch-clamp analysis of currents in identified sensory neurons. Three distinct classes of voltage-sensitive potassium conductances are characterized; all were detected in distal parts of ommatidia from sevenless mutants and hence in one cell class (R1-6 photoreceptors). Rapidly inactivating ...

Physiological adaptation to acute hypoxia involves oxygen-sensing by a variety of specialized cells including carotid body type I cells, pulmonary neuroepithelial body cells, pulmonary artery myocytes and foetal adrenomedullary chromaffin cells. Hypoxia induces depolarization by closing a specific set of potassium channels and triggers cellular responses. Molecular biology strategies have recen...

BACKGROUND Apamin sensitive potassium current (I KAS), carried by the type 2 small conductance Ca(2+)-activated potassium (SK2) channels, plays an important role in post-shock action potential duration (APD) shortening and recurrent spontaneous ventricular fibrillation (VF) in failing ventricles. OBJECTIVE To test the hypothesis that amiodarone inhibits I KAS in human embryonic kidney 293 (HE...

We examined the hypothesis that dilatation of the basilar artery in response to activation of ATP-sensitive potassium channels is impaired in stroke-prone spontaneously hypertensive rats (SHRSP). Changes in basilar artery diameter in response to aprikalim, a direct activator of ATP-sensitive potassium channels, were measured in anesthetized SHRSP and normotensive Wistar-Kyoto (WKY) rats through...

ATP sensitive potassium (KATP) channels are metabolic sensors with channel activity promoted by decreases in ATP andnor increases in MgADP. The most studied are channels present in cardiac myocytes and pancreatic b cells but KATP currents also exist more widely in a range of tissues and organs [1,2]. The channel is a hetero-octamer comprising four sulphonylurea receptors and four pore-forming i...

introduction: we have recently reported the presence of two potassium currents with 598 and 368 ps conductance in the rough endoplasmic reticulum (rer) membrane. the 598 ps channel was voltage dependent and atp sensitive. however, the 368 ps channel was rarely observed and its identity remained obscure. since cationic channels in intracellular organelles such as mitochondria and rer play import...

Neutrophil activation and migration during an inflammatory response is preceded or accompanied by plasma membrane electrical changes. Besides changes in calcium currents, neutrophils have a high permeability to potassium, mainly through potassium channels. However, the significance of potassium channels in neutrophil physiology is still unclear. Here, we show that the treatment of rats with the...

ATP-sensitive potassium (KATP) channel openers have a relaxation effect due to the lower cellular membrane potential and inhibit calcium influx. There has been considerable interest in exploring KATP channel openers in the treatment of various diseases such as cardiovascular, cerebrovascular, and urinary system disease and premature labor. The purpose of this study was to synthesize 3,3,6,6-tet...