Mucous secretions

Asthma is a complex respiratory disorder that involves mast cell degranulation, mucous secretions, and smooth muscle hypertrophy and hyperresponsiveness. Smooth muscle hyperresponsiveness has suggested some defect in the regulation of smooth muscle contractility. Therefore, a number of studies concerning asthma have centered on whether alterations in the regulation of smooth muscle contraction (Figure 4) are responsible for hyperactivity in asthmatic airway smooth muscle. 

Phytochemicals influence other digestive secretions. Several traditional herbal medicines stimulate gastric mucous secretion, providing protection (Sairam et al., 2001). The secretion and recycling of bile are also responsive to phytochemicals. The way in which certain polysaccharides increase fecal concentrations of bile acids (DalT Angelo and Lino van Poser, 2000) and thereby influence recycling and synthesis is particularly noteworthy. 

Recently, a novel class of prostaglandin derivatives, PG-1,15-lactones (Fig. 1) of both E [16] and F [17] series, has been reported to occur in the opisthobranch mollusc Tethys fimbria, along with smaller amounts of some of the corresponding PGs. Some lactones were present mainly in the mucous secretion and dorsal appendages known as cerata, while others were more abundant in the mantle. Fatty acid esters of PGF-1,15-lactones (C9 and Cu) were found only in T. fimbria eggmasses and reproductive glands (ovotestis). The structural variety of the lactones and the data on their distribution in the body... 

The content by weight of carbohydrate in glycoproteins may vary from only a few percent to over 50 percent in some proteins in mucous secretions. Although the function of the polysaccharide in most glycoproteins is unknown, in some cases it may provide hydrophilicity, recognition, and points of noncovalent interaction with other proteins through lectin-like affinity binding. 

Mild to Moderate — Immediate miosis (eye pain, headache behind the eyes, dim, blurred or tunnel vision), rhinorrhea, mild to severe mucous secretions and dyspnea. 

Within 30 minutes of their administration, 6 -adrenergic drugs often reverse most of the functional deficit in Monday morning byssinotics. As there is no mucous secretion, airway smooth muscle contraction is considered the primary response. Exposure of man to histamine aerosols produces pulmonary function changes similar to those seen after exposure to dust extract. However, exposure to histamine aerosol invariably initiates constriction of smooth muscle more rapidly than exposure to cotton dust ( <15 minutes), and dissipates within minutes, while the acute effects of inhalation of cotton dust and dust extracts lasts for hours. The slowly developing and prolonged effects of dust and extracts suggest that mediators other than histamine are involved. 

Dermal application of up to 2.6g/kg resulted in no deaths and no signs of percutaneous toxicity moderate irritation of the skin was observed. Instillation of the liquid into the eye of a rabbit produced erythema and edema of the conjunctiva, tearing, and mucous secretion but no corneal injury. 

Patients with CF suffer from thick mucous secretions in the airways as well as the pancreas and Intestinal lining due to impaired chloride absorption and consequent fluid imbalance. 

These thick mucous secretions are difficult for the mucociliary cells of the airway to clear, resulting In chronic airway obstruction, inflammation, and frequent lung infections. 

Patients with cystic fibrosis use aerosol inhaler sprays of the DNA-hydrolyzing enzyme deoxyribonuclease to help reduce the viscosity of mucous secretions, which contain large amounts of DMA arising from destruction of WBCs as they fight lung Infections. 

Ornithine decarboxylase activity. Cigarette smoke was administered to intact animals and animals with ulcers at concentrations of 2 or 4%. The treatment significantly reduced the thickness of the mucous secreting layer and gastric mucosal ornithine decarboxylase activity in animals with or without ulcers. The extract significantly reduced mucus synthesis and ornithine decarboxylase activity but not its mRNA expression in MKN-28 cells " . Cigarette smoke and its extract, in human MKN-28 cells, markedly decreased mucus synthesis in vivo and in vitro and suppressed ornithine decarboxylase activity . 

Expectorant. An agent that induces the removal (coughing up) of mucous secretion from the lungs. 

Cystic fibrosis is a life-threatening genetic disease caused by a dysfunctional cystic fibrosis transmembrane regulator, CFTR protein, which modulates salt and water transport into and out of cells. This ion-channel defect leads to poorly hydrated, thick, mucous secretions in the airways and severely impaired mucociliary func-... 

The mucous secretions are vital, as they act as lubricants and defensive agents, in cavities of the body communicating with the environment, or on body surfaces.229 415 418 452 The influence of sialic acids on the macromolecular conformation seems to be the reason for the proteolytic resistance of several sialo-glycoproteins. The first example of such a role for sialic acids came from studies by Faillard and Pribilla453 that demonstrated a loss of the... 

Interaction with local tissues. Sucralfate appears to augment the protective function of the mucous-bicarbonate barrier, partly due to increased bicarbonate and mucous secretion, and partly to an interaction with the unstirred layer overlying gastric epithelium, as well as by making the mucous gel more hydrophobic. It binds bile acids and pepsin and adheres to both ulcerated and nonulcerated mucosa. 

Increased lower airway mucous secretion Relaxation vascular smooth muscle Positive inotropy Slows AV conduction... 

Denny, M. W. (1989). Invertebrate mucous secretions Functional alternatives to vertebrate paradigms. Symp. Soc. Exp. Biol. 43, 337-366. 

Winter flounder Skin mucous secretion Pleurocidin Cole et al. (1997)... 

Because of their large number of negative charges, these heteropolysaccharide chains tend to be extended in solution. They repel each other and are surrounded by a shell of water molecules. When brought together, they "slip" past each other, much as two magnets with the same polarity seem to slip past each other. This produces the "slippery" consistency of mucous secretions and synovial fluid. When a solution of glycosaminoglycans is compressed,... 

Vitamin A, as retinal, has a clearly established role in vision (Chapter 23) and apparently has a specialized function in reproduction. In vitamin A deficiency no sperm cells are formed in males, and fetal resorption occurs in females. Rats deprived of vitamin Abut fed retinoic acid become blind and sterile but otherwise appear healthy.e bb Evidently either the alcohol or the aldehyde has an essential function in reproduction, whereas bone growth and maintenance of mucous secretions requires only retinoic acid. Indeed, retinoic acid is 100 to 1000 times more active than other forms of vitamin A in these differentiation functions.1 ... 

In vitamin A deficiency the internal epithelial surfaces of lungs and other tissues, which are usually rich in mucous secreting cells and in ciliated cells, develop thick layers of keratinizing squamous cells similar to those on the external surface of the body. 

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