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Exocrine Secretion (exocrine + secretion)
Selected AbstractsThe effect of feeding time (day versus night) and feeding frequency on pancreatic exocrine secretion in pigsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1 2000J. A. M. Botermans The effect of night feeding and feeding frequency on exocrine pancreatic secretion was studied in five chronically catherized growing pigs (16 to 31 kg). Feeding during the night (2200 to 2400 h) as compared to the day (1000 to 1200 h) tended to stimulate cholesterol ester lipase activity and tended to lower the colipase : lipase ratio in the pancreatic juice, but no effect on volume output, protein output and the activities of trypsin, chymotrypsin, amylase, lipase and colipase could be demonstrated. Feeding 12 small meals between 0800 and 2000 h as compared to one large meal (1000 to 1200 h) daily, altered the pattern of exocrine pancreatic secretion, tended to stimulate protein output by 44 %, chymotrypsin activity by 29 % and lipase activity by 46 %. These observations strengthened the theory that exocrine pancreatic secretion is partly regulated by feed intake per se and does not only depend on the amount of feed consumed. Feeding 12 small meals versus one large meal, compared at the same total daily feed intake, lowered the colipase : lipase ratio by 32 %. It can be concluded that feed intake pattern affected exocrine pancreatic secretion. [source] Utilizing endocrine secretory pathways in salivary glands for systemic gene therapeutics,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2004Antonis Voutetakis Mammalian salivary glands are commonly used models of exocrine secretion. However, there is substantial experimental evidence showing the physiological existence of endocrine secretory pathways in these tissues. The use of gene transfer technology in vivo has allowed the unambiguous demonstration of these endocrine pathways. We and others have exploited such findings and evaluated salivary glands as possible target tissues for systemic applications of gene therapeutics. Salivary glands present numerous advantages for this purpose, including being well encapsulated, which limits extra-glandular vector dissemination, and having the luminal membranes of almost all parenchymal cells accessible via intraoral delivery of vectors through the main excretory ducts. Existing studies suggest that clinical benefits will result from salivary gland targeted systemic gene therapeutics. J. Cell. Physiol. 199: 1,7, 2004. Published 2003 Wiley-Liss, Inc. [source] Stimulatory Effect of N -Methyltyramine, a Congener of Beer, on Pancreatic Secretion in Conscious RatsALCOHOLISM, Issue 2010Eri Tsutsumi Background:, Alcoholic beverages stimulate gastric acid secretion and increase the appetite. Although ingested ethanol stimulates pancreatic secretion, alcoholic beverages contain several congeners. N -methyltyramine (NMT) was isolated from beer as a factor in stimulating gastric acid secretion. In this study, we examined NMT to determine whether the congener stimulated pancreatic secretion in conscious rats. Methods:, Cannulae were inserted into male Wistar rats to separately drain bile and pancreatic secretions: 2 duodenal cannulae, a gastric cannula, and an external jugular vein cannula. The rats were placed in modified Bollman-type restraint cages. After a 4-day recovery period, experiments were conducted on unanesthetized rats. Different concentrations of NMT (5, 25, and 50 ,g/kg) solutions were infused into the stomach. To examine the mechanism, the effects of the proton pump inhibitor, cholecystokinin (CCK-BR) antagonist (YM022), CCK-AR antagonist (CR1505), and atropine were administered prior to the NMT (25 ,g/kg) infusion. The effect of intravenous infusion of NMT (7.5 ,g/kg) was then determined. Moreover, dispersed acini were prepared, and the effect of different concentrations of NMT on amylase release was determined. Results:, Intragastric administration of NMT significantly increased pancreatic exocrine secretion in a dose-dependent manner. Atropine eliminated the stimulatory effect of NMT, but the infusion of the proton pump inhibitor, YM022, and CR1505 did not. Intravenous infusion of NMT did not affect pancreatic secretion, and NMT did not stimulate amylase release in vitro. Conclusions:,N -methyltyramine stimulates pancreatic secretion via the cholinergic gastro-pancreatic reflex. The NMT content in beer was 2 mg/l, so that if a person weighing 60 kg consumes a 750 ml of beer, 25 ,g/kg NMT will be ingested. Therefore, the stimulatory effect of beer on pancreatic secretion was produced not only by ethanol but also by the congener, NMT. [source] Effect of P2X7 receptor knockout on exocrine secretion of pancreas, salivary glands and lacrimal glandsTHE JOURNAL OF PHYSIOLOGY, Issue 18 2010Ivana Novak The purinergic P2X7 receptors are expressed in different cell types where they have varied functions, including regulation of cell survival. The P2X7 receptors are also expressed in exocrine glands, but their integrated role in secretion is unclear. The aim of our study was to determine whether the P2X7 receptors affect fluid secretion in pancreas, salivary glands and tear glands. We monitored gland secretions in in vivo preparations of wild-type and P2X7,/, (Pfizer) mice stimulated with pilocarpine. In cell preparations from pancreas, parotid and lacrimal glands we measured ATP release and intracellular Ca2+ activity using Fura-2. The data showed that pancreatic secretion and salivary secretions were reduced in P2X7,/, mice, and in contrast, tear secretion was increased in P2X7,/, mice. The secretory phenotype was also dependent on the sex of the animal, such that males were more dependent on the P2X7 receptor expression. ATP release in all cell preparations could be elicited by carbachol and other agonists, and this was independent of the P2X7 receptor expression. ATP and carbachol increased intracellular Ca2+ activity, but responses depended on the gland type, presence of the P2X7 receptor and the sex of the animal. Together, these results demonstrate that cholinergic stimulation leads to release of ATP that can via P2X7 receptors up-regulate pancreatic and salivary secretion but down-regulate tear secretion. Our data also indicate that there is an interaction between purinergic and cholinergic receptor signalling and that function of the P2X7 receptor is suppressed in females. We conclude that the P2X7 receptors are important in short-term physiological regulation of exocrine gland secretion. [source] Juvenile hormone,stimulated synthesis of acyl-glycerols and vitamin E in female accessory sexual glands of the fire bug, Pyrrhocoris apterus L.ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2009Pavel Jedli Abstract Secretory cells of the female accessory sexual glands (AG) of P. apterus grow and produce yellow oily exocrine secretion in response to stimulation by endogenous juvenile hormone (JH) or exogenous treatments by JH analogues. The secretion determines the property of future egg shells by coating the chorion surface of the oocytes that are passing individually through the common uterus during oviposition. Diapausing females with a physiologically inhibited endocrine system or females with artificially removed hormonal sources show inactive ovaries and empty AG without the secretory products. Ovary-ectomised females with the intact neuroendocrine system develop hypertrophic AG loaded with the oily secretion. This shows that there is no direct dependence between formation of the oily secretion in AG and ovarian growth. Chemical analysis of the secretory products revealed the presence of acetylated glycerols, with the most abundant stearoyl-diacetyl-glycerol, stearoyl-acetyl-propionyl-glycerol, and the corresponding derivatives of arachidonic acid. In addition to this, the JH-activated secretory cells of AG also produced , - and , -tocopherols. The possible antioxidant or antimutagenic action of these vitamin E compounds in insect reproduction has been emphasized. © 2009 Wiley Periodicals, Inc. [source] Current issues in Sjögren's syndromeORAL DISEASES, Issue 3 2002Roland Jonsson Sjögren's syndrome is a chronic autoimmune and rheumatic disorder with prominent sicca complaints from the mucous membranes because of lack of proper exocrine secretions. There is no straightforward and simple diagnostic test for Sjögren's syndrome, although several classification criteria have been designed including several oral diagnostic tests. A new set of classification criteria in a joint effort by research groups in Europe and USA has recently been presented. A large number of autoantibodies have been reported in Sjögren's syndrome where, in some cases, the antibodies are correlated with the extent and severity of disease. The finding of serum autoantibodies directed against the muscarinic M3 receptor is an important advance in understanding the pathogenesis of not only the impaired glandular function but also associated features of autonomic dysfunction in some patients. The treatment of primary Sjögren's syndrome is still mainly symptomatic. [source] The role of nectar production, flower pigments and odour in the pollination of four species of Passiflora (Passifloraceae) in south-eastern BrazilBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2001ISABELA GALARDA VARASSIN The pollination biology of four species of passionflower was studied in south-eastern Brazil, specifically the importance of chemical features of floral nectar, pigments and odours. All species required pollinators to produce fruits: P. alata was pollinated by bees, P. speciosa by hummingbirds, and P. galbana and P. mucronata by bats. Pollinators consumed nectar as a food source. The activity of vertebrate pollinators reflected resource availability: they foraged when large amounts of nectar were available and when quantitative resource predictability was greater. The nectar of the vertebrate-pollinated species was richer in cholesterol and phospholipids, and had a potassium-sodium ratio higher than 1.0. For all species, the light absorption of flowers was paralleled by the pollinators' visual spectral sensitivity. This first report on Passiflora floral volatile compounds showed that there was a greater chemical class diversity among the species pollinated by animals with an acute olfactory sense, such as bees and bats. Benzenoid alcohols were the most represented compounds. The fragrances contained compounds that occur in other plant species and in the exocrine secretions of bees. This study shows a strong association between pollinators and the attracting and rewarding features of flowers. [source] | |||||||||||||