Cholinergic blockers

Substance which remain in the stomach for a long time Barbital, aspirin, iron, alcohol, cholinergic blockers, narcotic drugs, phenytoin, antidepressants. 

Erection occurs when adrenergic-induced sinusoid tone is antagonized by sacral parasympathetic stimulation that produces sinusoidal relaxation primarily by synthesis and release of the nonadrenergic-noncholinergic (NANC) neurotransmitter nitric oxide (NO). The contribution of acetylcholine-dependent release of NO from the vascular endothelium is uncertain. In vitro electrical stimulation of isolated corpus cavemosum strips (with or without endothelium) produces sinusoidal relaxation by release of neurotransmitters within nerve terminals that is resistant to adrenergic and cholinergic blockers. Inhibitors of the synthesis of NO or of guanosine monophosphate (GMP),... 

On the other hand, 5-HT1A receptor antagonists have been shown to attenuate or reverse the cognitive deficits induced by the cholinergic blocker scopolamine, which might suggest a new therapeutic activity for this drug class (203,204). 

Standard post-exposure treatments include eoneurrent administration of anticholinergics, such as the musearinie cholinergic blocker atropine sulfate, and AChE reactivators, such as obidoxime and pyridine-2-aldoxime methochloride (also known as 2-PAM). Oximes cannot reactivate OP-inhibited AChE that has already aged . Therefore, traditional oxime treatment is considered to be less effective for those agents such as soman, for which aging is rapid (Worek et al, 2005). 

The moderately sedating group of antihistamines should not be used when operating hazardous equipment or when good motor and sensory skiUs are required. Some of these agents, such as clemastine, are moderately potent cholinergic blockers. 

Synonyms Parasympatholytics Cholinergic blockers Sympatholytics Antispasmodics... 

Miosis, pain, dim vision, and nausea may be relieved by topical atropine in the eye. Atropine, a cholinergic blocker or anticholinergic drug, is effective in blocking the effects of excess acetylcholine at peripheral muscarinic sites. The usual dose is 2 mg for minor exposures and 6 mg for severe exposures. 

Cholinesterase inhibitors benefit certain patients (Bartus et al, 1982). The central cholinergic blocker, scopolamine, induces memory dysfunction resembling aging and Alzheimer s disease in young, normal subjects. Phy-sostigmine reverses these scopolamine-induced defects in memory and cognition. However, the response is different in patients with Alzheimer s disease the improvements with physostigmine have been erratic and... 

Propranolol may increase procainamide plasma levels. Additive cholinergic effects may occur when procainamide is administered with other drugp with anticholinergic effects. There is the potential of additive cardiodepressant effects when procainamide is administered with lidocaine. When a beta blocker, such as Inderal, is administered with lidocaine, there is an increased risk of lidocaine toxicity. 

Batra S (1990) Interaction of antiestrogens with binding sites for muscarinic cholinergic drugs and calcium channel blockers in cell membranes. Cancer Chemother Pharmacol 26 310-312... 

Hirschhom ID, Rosecrans JA (1973) Nicotine as a discriminative stimulus the time course of the cue and the effect of receptor blockers. The Pharmacologist 15 236 Hirschhom ID, Rosecrans JA (1974) Studies on the time course and the effect of cholinergic and adrenergic receptor blockers on the stimulus effect of nicotine. Psychopharmacologia 40 109-120... 

Imidazole-2-diazonium fluoroborate is an irreversible blocker of the phencyclidine binding site of the nicotinic cholinergic receptor, and it is only effective when the receptor is in a desensitized state, at variance with other aryldiazonium salts (85MI1). 

Belladonna alkaloids have an extremely broad pharmacological spectrum. In addition to their ability to block M-receptors, atropine and scopolamine also act on other receptors, thus showing corresponding effects. They can only block nicotinic cholinergic receptors, however, in significantly larger doses than those used in clinics. Atropine also exhibits properties of local anesthetics and histamine (Hj) receptor blockers. Atropine and... 

L C. Rapacuronium is a skeletal muscle relaxant that works by competing with ACh for receptors at the postjunctional membrane. Nicotine and succinylcholine also act at the end plate receptors but cause depolarization. Hexamethonium is a ganglion blocker that has essentially no activity at the end plate receptors, and scopolamine blocks cholinergic muscarinic receptors and thus does not act at the end plate receptors. 

Metrifonate is an organophosphorous compound that is effective only in the treatment of S. haematobium The active metabolite, dichlorvos, inactivates acetylcholinesterase and potentiates inhibitory cholinergic effects. The schistosomes are swept away from the bladder to the lungs and are trapped. Therapeutic doses produce no untoward side effects except for mild cholinergic symptoms. It is contraindicated in pregnancy, previous insecticide exposure, or with depolarizing neuromuscular blockers. Metrifonate is not available in the United States. 

Two general types of neuromuscular blockers are discussed here. They are classified according to those that depolarize the skeletal muscle cell when binding to the cholinergic receptor and those that do not.37... 

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