Bicarbonate transport in microperfused pancreatic ducts

Bicarbonate transport in microperfused pancreatic ducts.

Substance P inhibits bicarbonate secretion from guinea pig pancreatic ducts by modulating an anion exchanger.

The stimulatory pathways controlling HCO3- secretion by the pancreatic ductal epithelium are well described. However, only a few data are available concerning inhibitory mechanisms, which may play an important role in the physiological control of the pancreas. The aim of this study was to investigate the cellular mechanism by which substance P (SP) inhibits pancreatic ductal HCO3- secretion. Sm...

Aquaporins in rat pancreatic interlobular ducts.

The aquaporin (AQP) family of water channels is distributed ubiquitously in many epithelia and plays a fundamental role in transmembrane water transport. The aim of this study is to identify the water transport pathway in pancreatic duct cells where most of the HCO-rich fluid originates. Using digital videomicroscopy, we measured the osmotic water permeability (P(f)) of pancreatic duct epitheli...

Impaired pancreatic bicarbonate secretion in chronic malnutrition.

Twenty three children with recurrent episodes of diarrhea and chronic malnutrition were studied for pancreatic duct function. Those children were subjected to pancreatic stimulation with pancreozymin and secretin. Grade I malnourished children, as per Gomez classification, formed the control group. The water output from pancreas increased in malnourished children (p < 0.05). It correlated signi...

Bicarbonate transport in cell physiology and disease.

The family of mammalian bicarbonate transport proteins are involved in a wide-range of physiological processes. The importance of bicarbonate transport follows from the biochemistry of HCO(3)(-) itself. Bicarbonate is the waste product of mitochondrial respiration. HCO(3)(-) undergoes pH-dependent conversion into CO(2) and in doing so converts from a membrane impermeant anion into a gas that ca...