Mechanism of secretion

Dunant, Y (1994) Hormone and neurotransmitters release four mechanisms of secretion. Cell Biol. Int. 18 327-336. 

Elhamdani A, Azizi F, Artalejo CR. 2006. Double patch clamp reveals that transient fusion (kiss-and-run) is a major mechanism of secretion in calf adrenal chromaffin cells High calcium shifts the mechanism from kiss-and-run to complete fusion. J Neurosci 26 3030-3036. 

Loratadine is well absorbed after oral administration, with peak plasma concentrations at approximately 1.5 hours. Clinically significant relief of symptoms is usually obtained within 2 to 4 hours of the first dose. Excretion of loratadine occurs almost equally through the urine and feces.This dual mechanism of secretion provides a measure of safety in patients with liver or kidney disease, but caution should be exercised in both groups. Also, torsades de pointes may occur with the concurrent use of loratadine and amiodarone. Desloratadine is a metabolite of loratadine. 

Yasue H, Yoshimura M, Sumida H, Kikuta K, Kugiyama K, Jougasaki M, et al. Localization and mechanism of secretion of B-type natriuretic peptide in comparison with those of A-type natriuretic peptide in normal subjects and patients with heart failure. Circulation 1994 90 195-203. 

The bile acids are 24-carbon steroid derivatives. The two primary bile acids, cholic acid and chenodeoxycholic acid, are synthesized in the hepatocytes from cholesterol by hy-droxylation, reduction, and side chain oxidation. They are conjugated by amide linkage to glycine or taurine before they are secreted into the bile (see cholesterol metabolism. Chapter 19). The mechanism of secretion of bile acids across the canalicular membrane is poorly understood. Bile acids are present as anions at the pH of the bile, and above a certain concentration (critical micellar concentration) they form polyanionic molecular aggregates, or micelles (Chapter 11). The critical micellar concentration for each bile acid and the size of the aggregates are affected by the concentration of Na+ and other electrolytes and of cholesterol and lecithin. Thus, bile consists of mixed micelles of conjugated bile acids, cholesterol, and lecithin. While the excretion of osmotically active bile acids is a primary determinant of water and solute transport across the canalicular membrane, in the canaliculi they contribute relatively little to osmotic activity because their anions aggregate to form micelles. 

Source Davenport HW. The mechanism of secretion of sulfonamide drugs in gastric juice. Yale J Biol Med 14 591,1942. 

I sent the paper for publication within a week of obtaining the last datum. I knew the analysis of the mechanism of secretion of sulfonamide drugs had little importance in itself, but I was pleased to have pulled the physiological rabbit out of the physicochemical hat. 

Figure 1 -22. Essentials of a mechanism of gastric secretion displaying maximum efficiency proposed by R. E. Davies and A. G. Ogston in 1950. (Adapted from Davies RE, Ogston AG. On the mechanism of secretion of ions by gastric mucosa and other tissues. Biochem 146 324-333, 1950.)...

As a teacher of physiology at St. Bartholomew s Hospital Medical School in London, John Sydney Edkins was well aware of Bayliss and Starling s discovery. " He was also aware of the problem of the control of gastric secretion, for he had contributed a chapter on Mechanisms of Secretion of Gastric, Pancreatic, and Intestinal Juices to Schafer s Text-book of Physiology, published in 1898. ... 

Davies RE, Ogston AG. On the mechanism of secretion of ions by gastric mucosa and other tissues. Biochem J 46 324-333, 1950. 

Mechanisms of secretion in Gram negative bacteria have been elucidated (with either a Wzx-Wzy-dependent pathway or an ABC transporter-dependent pathway [58]) but very little is known in fungi. Even in the rather well-studied A. pullulans, mechanisms of pullulan secretion remain unclear and no secretory enzyme has been identified [59,60]. Yoneda et al. [49] demonstrated only recently that the cryptococcal capsule was synthesized intracellularly and secreted via exocytosis. It is clear from these few examples that the wide diversity of the molecular structures formd in EPS implies a wide variety of synthetic routes, difficult to identify. 

Measurement, General Techniques and Criteria, 3, 5-7 Mechanism of Secretion distal tubules, 98 proximal tubules, 98 Microanalysis - variables, K" , 77 Microelectrodes... 

Park, S.W., Lawrence, C.B., Linden, J.C. and Vivanco, J.M. (2002) Isolation and characterization of a novel ribosome-inactivating protein from root cultures of pokeweed and its mechanism of secretion from roots. Plant Physiol. 130, 164—178... 

Rosenau F, Jaeger KE (2000) Bacterial lipases from pseudomonas regulation of gene expression and mechanisms of secretion. Biochimie 82 1023-1032 Rubin EM (2008) Genomics of cellulosic biofuels. Nature 454 841-845 Ruiz C, Blanco A, Javier Pastor FI, Diaz P (2002) Analysis of Bacillus megaterium lipolytic system and cloning of LipA, a novel subfamily 1.4 bacterial lipase. EEMS Microbiol Lett 217(2) 263-267... 

Cellular aspects of protein polysaccharide synthesis, including intracellular sites of synthesis, mechanism of secretion, and regulation of polysaccharide biosynthesis in the intact cell. 

Although it is possible to list all of the mammalian secretory cells and to note in some detail the biochemical nature of both precursor material and final secretory product, as well as to describe the intracellular pathway of secretory product formation, this would defeat the purpose of the current discourse. Rather, it will be more instructive to examine one secretory cell in detail and to compare it to several other representative cell types. From this analysis, one may derive an overview of the general mechanisms of secretion. For this purpose, I have chosen as a starting point the pancreatic exocrine cell because this cell has been one of the most thoroughly investigated, and its secretory pattern provides an ideal model on which to build broad concepts. 

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