Histamine cyclic adenosine 3 : 5 monophosphate , inhibition

The Hi Receptor and its Ligands. The H receptor mediates effects, through an increase in cyclic adenosine monophosphate (cAMP). such as gastric acid secretion relaxation of airway smooth muscle and of pulmonary vessels increased lower airway mucus secretion esophageal contraclion inhibition of basophil, but not mas cell histamine release inhibition of neutrophil activation and induction or suppressor T cells. There is no evidence that the H- receptor causes significant modulation of lung function in the healthy human subject or in the asthmatic. 

Colchicine with its microtubule-disrupting properties limits the chemotactic and phagocytic activity of polymorphonuclear lymphocytes. It also induces the release of prostaglandin E, a suppressor of leukocyte function by increasing the level of cyclic adenosine monophosphate [39]. Furthermore, the ability of colchicine in inhibition of IL-1 production and histamine release makes it an excellent drug for a number of dermatitis-related complexities like psoriasis, Behget s syndrome, recurrent aphthous stomatitis, leukocytoclastic vasculitis and urticarial vasculitis, bullous disease, scleroderma, fibromatosis. Sweet s syndrome, amyloidosis, and many more [40]. 

The role of cyclic adenosine monophosphate, prostaglandins, and catecholamines in the regulation of mediator release - In 1936, long before the role of catecholamines in the control of adenyl cyclase was appreciated, Schild 2 described the inhibition of the release of histamine from guinea pig lung by epinephrine. It remained for Lichtenstein and Margolis, however, to revive interest in this area. Data have now been accumulated... 

Cyclic AMP. Drugs such as the 8-adrenoceptor agonists, methylxanthines, prostaglandins and histamine Itself cause an increase in mast cell or basophil levels of cyclic adenosine 3 5 monophosphate, and this is associated with inhibition of histamine secretion Induced by an immunological stimulus (49,50,51). Whilst cyclic AMP itself does not inhibit histamine secretion Induced by an immunological stimulus, the dlbutyryl derivative which is able to pass through cell membranes is an inhibitor of secretion (52, 54), as is adenosine 3 5 cyclic phosphorothioate, which also passes into cells (53). 

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