The acid- and volume-sensitive TASK2 K+ channel is strongly expressed in renal proximal tubules and papillary collecting ducts. This study was aimed at investigating the role of TASK2 in renal bicarbonate reabsorption by using the task2 -/- mouse as a model. After backcross to C57BL6, task2 -/- mice showed an increased perinatal mortality and, in adulthood, a reduced body weight and arterial bl...

Modes of bicarbonate entry from tubule lumen to cell were examined in isolated Ambystoma proximal tubules, using determinations of transepithelial potential differences (V3). (1) Upon removal of luminal substrate, tubules first equilibrated in bilateral (lumen and bath) 94.72 mM Cl- and 10 mM HCO3- yielded a change in V3 between the experimental and control circumstances of +1.8 mV (delta V3). ...

Carlin, Ryan W., Rebecca R. Quesnell, Ling Zheng, Kathy E. Mitchell, and Bruce D. Schultz. Functional and molecular evidence for Na -HCO3 cotransporter in porcine vas deferens epithelia. Am J Physiol Cell Physiol 283: C1033–C1044, 2002. First published May 22, 2002; 10.1152/ ajpcell.00493.2001.—This study focused on the role of sodium-bicarbonate cotransporter (NBC1) in cAMP-stimulated ion tran...

cAMP is an evolutionary conserved, prototypic second messenger regulating numerous cellular functions. In mammals, cAMP is synthesized by one of 10 homologous adenylyl cyclases (ACs): nine transmembrane enzymes and one soluble AC (sAC). Among these, only sAC is directly activated by bicarbonate (HCO3(-)); it thereby serves as a cellular sensor for HCO3(-), carbon dioxide (CO2), and pH in physio...

An electrogenic Na+/HCO3- cotransport system was studied in freshly dissociated Müller cells of the salamander retina. Cotransporter currents were recorded from isolated cells using the whole-cell, voltage-clamp technique following the block of K+ conductance with external Ba2+ and internal Cs+. At constant pHo, an outward current was evoked when extracellular HCO3- concentration was raised by ...

We investigated membrane voltage and intracellular pH (pHi) in cultured human ciliary muscle cells using a cell line (H7CM) and primary-cultured human ciliary muscle cells. 1) Resting potential was 58.9 +/- 1.0 mV in H7CM cells and 61.9 +/- 1.4 mV in primary cultures. The following data are from H7CM cells, but results from primary cultures were basically similar. 2) In HCO3(-)-CO2-buffered sol...

1. The effect of parathyroid hormone on gastric bicarbonate secretion was determined in the anaesthetized guinea pig. Subcutaneous injections of bovine parathyroid hormone (75 U.S.P units day-1 kg-1) for 7 days caused a significant increase in HCO3- output. There was also a rise in K+ output and a slight elevation of H+ secretion. A similar increase in HCO3- output occurred after acute intraven...

The aim of this work was to characterize the changes in pH regulation that lead to increased intracellular pH (pHi) in well-spread cells on tissue culture plastic relative to cells on a nonadhesive surface. Bicarbonate was not required for maintenance of a control steady state pHi or of the difference in pHi between round and spread cells. In the absence of bicarbonate, lowering the sodium cont...

Abstract This study reported the results of groundwater quality for drinking and irrigation purposes in Kurukshetra district, Haryana, India. Twelve parameters, namely pH, TDS, TH, sodium (Na+), magnesium (Mg2+), calcium (Ca2+), potassium (K+), chloride (Cl−), sulfate (SO42−), bicarbonate (HCO3−), nitrate (NO3−), fluoride (F−) were evaluated Water Quality Index (WQI) was calculated. Based on WQ...

A 36 year-old 5 weeks postpartum lactating woman presented to the emergency room with severe nausea and vomiting for 48 hours. The patient was found to be in non-diabetic ketoacidosis with a serum pH 6.9 and a HCO3 of <5mEq/L. This condition rapidly improved with the administration of intravenous dextrose and bicarbonate and with the cessation of breast feeding. The course and pathophysiology o...