Publications by authors named "John P Hayslett"

Background: Transient diabetes insipidus may rarely present during late pregnancy and/or the immediate puerperium, and if unrecognized, may cause neurologic injury and threaten the lives of mother and fetus. However, when recognized early and treatment is initiated with desmopressin acetate, an analog of vasopressin that is resistant to vasopressinase, water loss in the urine is eliminated and complications may be abrogated. This report aims to increase the awareness of this disorder and describes appropriate treatment.

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The purpose of this study was to determine whether there is a correlation between phosphorylation and activity of the epithelial sodium channel (ENaC). The three subunits that form the channel were immunoprecipitated from A6 cells by using specific polyclonal antibodies after labeling cells with (35)S or (32)P. When immune complexes were resolved on SDS-PAGE, the alpha-subunit migrated at 85 and 65 kDa, the beta-subunit at 115 and 100 kDa, and the gamma-subunit at 90 kDa.

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Unlabelled: In this prospective, randomized, placebo-controlled, double-blinded study, we determined the effects of two commonly used adjuncts, mannitol and dopamine, on beta(2)-microglobulin (beta(2)M) excretion rates in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass (CPB). beta(2)M excretion rate has been described as a sensitive marker of proximal renal tubular function. One-hundred patients with a preoperative serum creatinine level View Article and Find Full Text PDF

There are conflicting reports in the literature regarding the adenosine receptor that mediates the increase in sodium transport in the A6 cell. In this study we used specific A1 and A2 adenosine receptor agonists and antagonists, as well as two different subclones of the A6 cell, to determine which adenosine receptor mediates the increase in sodium transport. In the A6S2 subclone, basolateral and apical N6-cyclohexyladenosine (CHA), a selective A1 receptor agonist, stimulated sodium transport at a threshold concentration <10(-7) M, whereas CGS-21680, a selective A2 receptor agonist, had a threshold concentration that was at least 10(-5) M.

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The natriuretic effect of Ca(2+) channel blockers has been attributed to hemodynamic changes and to poorly defined direct tubular effects. To test the possibility that verapamil may inhibit Na(+) reabsorption at the distal tubule, its effect on transepithelial Na(+) transport in aldosterone-stimulated A6 cells was determined. Cells were grown on permeable supports, and short-circuit current (I(sc)) measured in an Ussing chamber was used as a surrogate marker for transepithelial Na(+) transport.

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