Muscle relaxants competitive

These compounds competitively inhibit phosphodiesterase, resulting in an increase in cyclic AMP (see Box 14.3) and subsequent release of adrenaline. This leads to the major effects a stimulation of the central nervous system (CNS), a relaxation of bronchial smooth muscle, and induction of diuresis. These effects vary in the three compounds. Caffeine is the best CNS stimulant, and has weak diuretic action. Theobromine has little stimulant action, but has more diuretic activity and also muscle relaxant properties. Theophylline also has low stimulant action and is an effective diuretic, but it relaxes smooth muscle better than caffeine or theobromine. 

Tubocurarine acts as a competitive inhibitor in the nicotinic acetylcholine receptor, meaning that the nerve impulse is blocked by this alkaloid. Tubocurarine is used in surgical practice as a muscle relaxant. These alkaloids have an observably large spectrum of activity and possible applications. Their utilization in the development of new applications is therefore relatively active in modern medicine. 

Magnesium sulfate, applied intravenously is often used as tocolytic. The mechanism of action is not completely clear but might involve a competition with calcium on the cellular level. Precautions in the sense of magnesium plasma level monitoring must be taken in patients with renal insufficiency since this divalent kation is eliminated by the kidneys. Relatively high plasma concentrations are necessary to achieve a sufficient tocolysis. The relatively frequent side effects are respiratory depression, depressed reflexes, headaches, palpitation and skin flushing in the mother and muscle relaxation and, rarely, CNS depression in the fetus. 

Faverin fluvoxamine. fazadinium bromide [ban. inn] is a bisquaternary amine complex heterocyclic compound, which acts as a NICOTINIC cholinoceptor ANTAGONIST, a (competitive) NEUROMUSCULAR BLOCKING AGENT. It can be used as a SKELETAL MUSCLE RELAXANT in anaesthesia, fazarabine [inn, usan] (Ara-Ac NSC 281272) is an analogue of cytarabine, an antimetabolite cytotoxic agent that has been used in ANTICANCER treatment. 

When ingested, GHB stimulates dopamine release, leading to pleasurable effects such as euphoria, muscle relaxation, and heightened sexual desire. It also has CNS depressant effects resulting in sedation and hypnosis. Because GHB was reported to enhance grovrth hormone release, it has been used as a steroid alternative by body builders and athletes. Athletes also have used GHB as a sleep aid because they believe it promotes rapid recovery from vigorous repetitive competition. These properties and the availability of GHB in dietary supplements led to growing recreational abuse of the... 

The best known clinical application of cholinesterase assay concerns the abnormally prolonged effect of the muscle relaxant succinylcholine that is found in a small proportion of patients. This compound, which was introduced into clinical medicine in the early 1950s (B29, B41, T47), owes its relaxant action to competition with acetylcholine for the receptors at the neuromuscular junction both cause depolarization of the muscle fibers, which contract. Acetylcholine is rapidly destroyed by acetylcholinesterase, so that repeated stimuli are applied to the muscle, causing a controlled contraction which persists as long as the nerve is stimulated. When, however, succinylcholine is administered, it is not destroyed by acetylcholinesterase, and its action persists until a large proportion of the dose has been hydrolyzed in the plasma. After initial contraction, the muscle fibers passively elongate to give the relaxation required by the anesthetist. 

Used mainly in anesthesia protocols or in the ICU to afford muscle relaxation and/or immobility. Occasionally used to treat tetanus. These muscle relaxants interact with nicotinic receptors at the skeletal muscle end plate. Nicotinic receptors are comprised of five subunits, two of which (alpha) bind ACh, a requirement for opening of the Na+ channel. Most drugs in this class bind competitively to one of the alpha subunits to prevent depolarization (receptor antagonists) one drug (succinylcholine) binds noncompetitively and opens the Na+ channel, causing excessive depolarization and desensitization. 

The skeletal muscle reiaxants provide muscle relaxation and/or immobility via N-receptor interactions. Most including d-tubocurarine, pancuronium, atracurium, and mivacurium, are competitive and nondepolarizing and can be reversed by AChE inhibitors. Succinylcholine is a depolarizing, noncompetitive agonist. 

Plant extract used by South American Indians to prepare poison arrows. Sold with different names (e.g. Tube-curare) depending on the container used for packaging. Toxicologically active principle is the alkaloid tubocurarine chloride. Muscle relaxant, toxic by respiratory paralysis and hypotension competitive blocker ACh receptor in muscle. 

A molecule called succinylcholine is a competitive inhibitor of acetylcholine binding to the receptor and can be used as a muscle relaxant in surgical procedures. This compound has a structure that resembles acetylcholine closely enough that it can bind to the acetylcholine receptor. However, it does not have the ability to stimulate muscle contraction. The result is that muscles relax. Normal muscle contraction resumes after infusion of the drug ceases. 

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