Biomaterial Database

Triglyceride formation and hydrolysis by toad bladder epithelium. 1969

A A Rosenbloom, and P Elsbach

Triglycerides of toad bladder epithelium have been labeled in vitro with either palmitate-1-(14)C or linoleate-1-(14)C, during incubation of bladders that had been cut in halves. Hydrolysis with pancreatic lipase of triglycerides labeled in this fashion revealed that palmitate-1-(14)C appeared predominantly in the 1- and 3-position, whereas half of linoleate-1-(14)C was located in the 2-position. The hydrolysis of palmitate-1-(14)C or linoleate-1-(14)C labeled triglycerides was examined in homogenates of isolated bladder mucosal cells. Lipase activity was evident from pH 3.5 to 8.0, but clearly greatest at pH 4.5. Below pH 6.0 the products of hydrolysis were fatty acid and monoglyceride and the 1- (or 3-) position was preferentially attacked; above pH 6.0 complete deacylation occurred. Acid-optimum hydrolysis of triglycerides with production of monoglycerides was linear for about 30 min. After 2 hr most of the labeled triglycerides were hydrolyzed. Repeated freezing and thawing of the homogenate enhanced lipase activity. Added Ca(++), previously shown to be required for phospholipase A activity in toad bladder, had no effect on hydrolysisof triglycerides. This lipase activity directed at the considerable store of triglycerides present in toad bladder epithelium may provide fatty acid for energy production or for synthesis of other esters such as in phospholipids.

UI	MeSH Term	Description	Entries
D008041	Linoleic Acids	Eighteen-carbon essential fatty acids that contain two double bonds.	Acids, Linoleic
D008049	Lipase	An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. (From Dorland, 27th ed) EC 3.1.1.3.	Triacylglycerol Lipase,Tributyrinase,Triglyceride Lipase,Acid Lipase,Acid Lipase A,Acid Lipase B,Acid Lipase I,Acid Lipase II,Exolipase,Monoester Lipase,Triacylglycerol Hydrolase,Triglyceridase,Triolean Hydrolase,Hydrolase, Triacylglycerol,Hydrolase, Triolean,Lipase A, Acid,Lipase B, Acid,Lipase I, Acid,Lipase II, Acid,Lipase, Acid,Lipase, Monoester,Lipase, Triglyceride
D008244	Lysophosphatidylcholines	Derivatives of PHOSPHATIDYLCHOLINES obtained by their partial hydrolysis which removes one of the fatty acid moieties.	Lysolecithin,Lysolecithins,Lysophosphatidylcholine
D009092	Mucous Membrane	An EPITHELIUM with MUCUS-secreting cells, such as GOBLET CELLS. It forms the lining of many body cavities, such as the DIGESTIVE TRACT, the RESPIRATORY TRACT, and the reproductive tract. Mucosa, rich in blood and lymph vessels, comprises an inner epithelium, a middle layer (lamina propria) of loose CONNECTIVE TISSUE, and an outer layer (muscularis mucosae) of SMOOTH MUSCLE CELLS that separates the mucosa from submucosa.	Lamina Propria,Mucosa,Mucosal Tissue,Muscularis Mucosae,Mucous Membranes,Membrane, Mucous,Membranes, Mucous,Mucosae, Muscularis,Mucosal Tissues,Propria, Lamina,Tissue, Mucosal,Tissues, Mucosal
D010169	Palmitic Acids	A group of 16-carbon fatty acids that contain no double bonds.	Acids, Palmitic
D010179	Pancreas	A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.
D010743	Phospholipids	Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.	Phosphatides,Phospholipid
D001743	Urinary Bladder	A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.	Bladder,Bladder Detrusor Muscle,Detrusor Urinae,Bladder Detrusor Muscles,Bladder, Urinary,Detrusor Muscle, Bladder,Detrusor Muscles, Bladder
D002247	Carbon Isotopes	Stable carbon atoms that have the same atomic number as the element carbon but differ in atomic weight. C-13 is a stable carbon isotope.	Carbon Isotope,Isotope, Carbon,Isotopes, Carbon
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol