Permeable anions such as chloride are required for ATP-evoked release of epinephrine and protein from isolated secretory vesicles (chromaffin granules) of the adrenal medulla. This reaction has been studied as a model for the exocytosis process, and we have found that the release reaction is a saturable function of ATP concentration at a variety of chloride concentrations. However, at constant ...

The effect of intravenous vasoactive intestinal polypeptide (VIP) on normal transport mechanisms in the human jejunum in vivo was examined with the triple-lumen, steady-state perfusion technique. By using special test solutions that revealed different aspects of jejunal transport, we were able to evaluate the effect of VIP on specific transport processes, such as active bicarbonate absorption, ...

Studies were carried out in normal male subjects (n = 6, age 20-35 years) to determine the interaction of angiotensin II and plasma sodium on aldosterone secretion. These relations were quantified by elevation of plasma sodium with an infusion of 5% sodium chloride (4 ml/kg/30 min i.v.) with measurements of plasma aldosterone, atrial natriuretic factor (ANF), and arginine vasopressin (AVP) over...

The sodium-coupled glucose transporter-1 (SGLT1)-based oral rehydration solution (ORS) used in the management of acute diarrhea does not substantially reduce stool output, despite the fact that glucose stimulates the absorption of sodium and water. To explain this phenomenon, we investigated the possibility that glucose might also stimulate anion secretion. Transepithelial electrical measuremen...

Lipid vesicles, especially giant lipid vesicles (GLVs), are usually adopted as cell membrane models and their preparation has been widely studied. However, the effects of some nonelectrolytes on GLV formation have not specifically studied so far. In this paper, nonelectrolytes, including sucrose, glucose, sorbitol ethanol, coexistence with sodium chloride, hydration were investigated. With meth...

AIMS It has been shown that optimizing atrioventricular (AV) and interventricular (VV) delay improves cardiac performance in patients with biventricular pacemakers. However, there is no standard method for optimization available yet. The aim of this study was to compare echocardiographic parameters-displacement imaging, A wave duration, and aortic velocity time integral (VTI)-and acoustic cardi...

The "Quantab" strip (Ames) measures chloride in fluids. For sodium chloride solutions and urine we found very good correlations between the Quantab reading and the chloride concentration as measured by chemical assay (r = 0.95 for chloride and r = 0.85 for sodium in urine). The strip gave reproducible results over the temperature range 4 to 37 degrees C. There was very little inter- and intra-o...

A significantly improved apparatus for the isopiestic measurement of thermodynamic activities at elevated temperatures is described. Details of the new design and of an analysis of the propagation of the experimental errors are presented. The apparatus was tested by measurements of calcium chloride against sodium chloride at 353.15 K. Accuracies of better than 0.1% in the osmotic coefficient ar...