Search results
Results from the WOW.Com Content Network
The pancreas also receives autonomic innervation. The blood flow into pancreas is regulated by sympathetic nerve fibers, while parasympathetic neurons stimulate the activity of acinar and centroacinar cells. Pancreatic secretion is an aqueous solution of bicarbonate originating from the duct cells and enzymes originating from the acinar cells.
The bicarbonate buffer system is an acid-base homeostatic mechanism involving the balance of carbonic acid (H 2 CO 3), bicarbonate ion (HCO − 3 ), and carbon dioxide (CO 2 ) in order to maintain pH in the blood and duodenum , among other tissues, to support proper metabolic function. [ 1 ]
The bicarbonate ion (hydrogencarbonate ion) is an anion with the empirical formula HCO − 3 and a molecular mass of 61.01 daltons; it consists of one central carbon atom surrounded by three oxygen atoms in a trigonal planar arrangement, with a hydrogen atom attached to one of the oxygens. It is isoelectronic with nitric acid HNO 3.
Ductal cells comprise about 10% of the pancreas by number and about 4% in volume. Its function is to secrete bicarbonate and mucins and to form the tubule network that transfers enzymes made by acinar cells to the duodenum. Ductal cells have a proliferation rate of about 0.5% in normal adults, but mitotic activity goes up when the pancreas is ...
Hydrogen ions secreted from the inner lining of the gallbladder keep the bile acidic enough to prevent hardening. To dilute the bile, water and electrolytes from the digestion system are added. Also, salts attach themselves to cholesterol molecules in the bile to keep them from crystallising. If there is too much cholesterol or bilirubin in the ...
Water is a very minor source of hydrogen ions in comparison to carbonic acid. Carbonic acid is formed from carbon dioxide and water by carbonic anhydrase. The bicarbonate ion (HCO 3 −) is exchanged for a chloride ion (Cl −) on the basal side of the cell and the bicarbonate diffuses into the venous blood, leading to an alkaline tide phenomenon.
The exocrine pancreas is one of two compartments that include digestive-acting acinar cells and duct cells.They represent an extension of the intercalated duct into each pancreatic acinus. [1] These cells are commonly known as duct cells , and secrete an aqueous bicarbonate solution under stimulation by the hormone secretin .
The alkaline tide is neutralised by a secretion of H + into the blood during HCO 3 − secretion in the pancreas. [2] Postprandial (i.e., after a meal) alkaline tide lasts until the acids in food absorbed in the small intestine reunite with the bicarbonate that was produced when the food was in the stomach. Thus, alkaline tide is self-limited ...