Membrane-stabilizing agents

Treatment of 2,6-dimethylaniline (121) with phosgene and triethylamine affords the corre-S]ionding isocyanate (122). Condensation of that reactive intermediate with N-isopropylpropyl-cne-1,3-diamine leads to formation of urea 123. This product, recainam (123), acts as membrane Stabilizing agent and thus exhibits both local anesthetic and antiarrhythmic activity [30]. 

Class I Local anesthetics or membrane-stabilizing agents that depress phase 0. 

The potassium-channel openers are thought to work by opening a subset of K -channels, which leads to membrane stabilization. Agents such as this have so far been proposed as vasodilators for the treatment of hypertension or heart failure, e.g. nicorandil. They may, however, become used for their smooth muscle relaxant action at other sites, e.g. in the aihvays as ANTIASTHMATIC AGENTS, or for bladder hyperexcitability. Other examples of drugs that work at least partly by this mechanism are cromakalim, diazoxide, pinacidil and minoxidil. See POTASSIUM-CHANNEL ACTIVATORS. 

Most channelopathies have some features in common. There are paroxysmal attacks of myotonia or paralysis, migraine, or ataxia precipitated by physiological stressors. They are often suppressed by membrane-stabilizing agents... 

The mechanism of action of certain membrane-stabilizing agents are described here under ... 

Discuss the synthesis of any one of the following membrane-stabilizing agents usually employed as cardiovascular drugs . 

Khattak, S. R, Bhatia, S. R., and Roberts, S. C. 2005. Pluronic fl 27 as a cell encapsulation material Utilization of membrane-stabilizing agents. Tissue Eng 11 974-83. 

A nonselective -blocker with some intrinsic sympathomimetic activity and a cell-membrane-stabilizing agent. 

Nadolol. Nadolol (Table 3) is a hydrophilic, nonselective -adrenoceptor blocking agent having no ISA and no membrane-stabilizing activity. It is useful for the treatment of hypertension and chronic stable exertional angina (98,99,108). 

Rudolph, A.S., Crowe, J.H. Crowe, L.M. (1986). Effects of three stabilizing agents - proline, betaine and trehalose on membrane phospholipids. Archives of Biochemistry and Biophysics, 245, 134-43. 

Pharmacology Flecainide has local anesthetic activity and belongs to the membrane stabilizing (Class I) group of antiarrhythmic agents it has electrophysiologic effects... 

Acebutolol (Sectral) is a cardioselective Pi-adrenocep-tor blocking agent that also has some minor membrane stabilizing effects on the action potential. 

Esmolol (Brevibloc) is a short-acting intravenously administered Pi-selective adrenoceptor blocking agent. It does not possess membrane-stabilizing activity or sympathomimetic activity. 

Local anesthetic action, also known as "membrane-stabilizing" action, is a prominent effect of several 8-blockers (Table 10-2). This action is the result of typical local anesthetic blockade of sodium channels and can be demonstrated experimentally in isolated neurons, heart muscle, and skeletal muscle membrane. However, it is unlikely that this effect is important after systemic administration of these drugs, since the concentration in plasma usually achieved by these routes is too low for the anesthetic effects to be evident. These drugs are not used topically on the eye, where local anesthesia of the cornea would be highly undesirable. Sotalol is a nonselective 8-receptor antagonist that lacks local anesthetic action but has marked class HI anti arrhythmic effects, reflecting potassium channel blockade (see Chapter 14 Agents Used in Cardiac Arrhythmias). 

A very interesting field in membrane bioreactors is the production of cyclodextrins or oligosaccharides. In general, they have applications in food pharmaceutical, cosmetic agricultural, and plastics industries as emulsifiers, antioxidant, and stabilizing agents. In the food industry cyclodextrins are employed for the preparation of cholesterol-free products. The use of enzymatic membrane reactors to produce... 

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