This study evaluates the cause of salinization in an irrigation scheme 100 ha supplied from a reservoir. The is located Gumselasa catchment (28 km2), Tigray region, northern Ethiopia. underlain by limestone–shale–marl intercalations with dolerite intrusion and some recent sediments. Water balance computation, hydrochemical analyses water quality methods were used this investigation. Surface wat...

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...

The gulf toadfish (Opsanus beta) intestine secretes base mainly in the form of HCO3- via apical anion exchange to serve Cl- and water absorption for osmoregulatory purposes. Luminal HCO3- secretion rates measured by pH-stat techniques in Ussing chambers rely on oxidative energy metabolism and are highly temperature sensitive. At 25 degrees C under in vivo-like conditions, secretion rates averag...

Calcitonin is known to stimulate Ca2+ reabsorption and natriuresis and to increase adenosine 3',5'-cyclic monophosphate levels in early distal tubule, but its effects on acid-base transport mechanisms are not well characterized in this segment. We found that recovery of cell pH (pH1) from an induced acid load (using NH4+) in single isolated segments of the initial portion ("bright") of the rabb...

Although increased Na+/H+ exchange (antiport) activity has been shown to precede both granulocytic and monocytic differentiation of HL60 cells, its requirement for this process remains controversial. We show here that, in the absence of HCO3-, the Na+/H+ exchanger is the predominant mechanism involved in rapid recovery of pHi from cytoplasmic acidosis; however, in the presence of HCO3-, other m...

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...

The electrogenic sodium bicarbonate cotransporter NBCe1 (SLC4A4) is a robust regulator of intracellular H(+) and a significant base carrier in many cell types. Using wild-type (WT) and NBCe1-deficient (NBC-KO) mice, we have studied the role of NBCe1 in cortical astrocytes in culture and in situ by monitoring intracellular H(+) using the H(+)-sensitive dye BCECF [2',7'-bis-(carboxyethyl)-5-(and-...

Microalgae are a large and diverse group of photosynthetic organisms which can use of solar energy to fixed inorganic carbon (Ci) with efficiency (2-10%) that are ten times greater than higher plants (<1%) due to their high growth rate (1to 3-fold increases in biomass per day) [1,2]. Although CO2 is the predominant carbon source for microalgal cultivation, the low level of dissolution of CO2 in...