What are m-holinoblokatory?

M-holinoblokatory - preparations well-known. These atropine-like drugs block the activity of the parasympathetic nervous system, its effect on the organs and glands of the body. Further in the article, the effects of m-holinoblokatorov, their importance in medicine, the effect and the scope of these drugs are described.

Classification

M-cholinoblockers are divided into three main groups:

1. Means "Atropine" and "Scopolamine", which are natural alkaloids.
2. Their semisynthetic derivatives, which differ from the initial substances, are the pharmacokinetic properties.
3. Synthetic compounds that may have selectivity for other subtypes of m-cholinergic receptors.

Properties

The agent "Atropin", being a reference preparation, is able to exert a stimulating effect on the activity of the central nervous system. Medication "Scopolamine" also has a sedative effect and is used for violations of gait, dizziness and other vestibular disorders. Contained in the tablets "Aeron" as an active substance, this compound is used to prevent seasickness.

The effect of m-holinoblokatorov "Atropin" and "Scopolamine" is different. The differences are most clearly marked when influencing the central nervous system. The drug "Scopolamine", in contrast to the drug "Atropine", has a central effect of pronounced character, even in small doses. This is due to the different permeability of the blood-brain barrier. This is the reason why m-holinoblokatory, containing atropine, are used much more often.

Of the semi-synthetic derivatives of natural alkaloids, the most important are the drugs "Gomatropin" and "Tropicamide", as well as "Methylatropine nitrate", "Bromide ipratropium" and "Tiotropium bromide". All these drugs are not able to penetrate the blood-brain barrier. To synthetic compounds of the third group include such m-holinoblokatory, such as "Pirenzepin" (prescribed for peptic ulcer diseases) and "Tolterodin" (recommended for incontinence).

Application

M-holinoblokatory (the mechanism of action of some of them will be described below) find their application in the quality of antispasmodics in colic of various kinds (renal, hepatic, intestinal), are prescribed with bronchospasm, and a decrease in the frequency of contractions in the heart. Medications are recommended for examination of the fundus, irite and iridocyclitis therapy, and atrial-ventricular conduction disorders.

The effect of m-holinoblokatorov, among other things, manifests itself in relaxing gastric and intestinal smooth muscles, reducing the secretion of the glands of digestion. Due to this, the funds can be used in the treatment of ulcers in both the stomach and duodenum. The drugs are also used as an antidote for intoxication with cholinomimetric and anticholinesterase components.

The effect of "Atropine" on the central nervous system

In moderate doses, which are 0.5-1 mg, the drug is only capable of sufficiently increasing the parasympathetic tone. This occurs as a result of excitation of the centers in the medulla oblongata and its overlying divisions. When the dosage is increased, the patient experiences an excited state, which is manifested by anxiety, disorientation, hallucinations. Very high doses give a braking effect, coma and paralysis can develop, cardiovascular insufficiency.

The effect of Scopolamine on the central nervous system

This drug is able to exert a retarding effect on the activity of the nervous system. It manifests itself in drowsiness, fatigue, a decrease in the proportion of fast sleep, and amnesia. Due to the ability to cause euphoria in some patients who abuse the drug, dependence is noted. Because of the sedative effect of the drug "Scopolamine" at one time wanted to use for general anesthesia. However, it was later revealed that, with severe pain, it is able even in therapeutic doses to cause anxiety, hallucinations and agitation. Acting on the cerebral cortex, the drug prevents motion sickness.

The effect of the drug "Atropine" on the cardiovascular system

The main effect of the drug is the change in the frequency of contractions in the heart. The drug can cause a pronounced tachycardia. However, when doses not exceeding permissible are used, the decrease in heart rate arises temporarily and does not lead to a change in blood pressure. It used to be assumed that such an effect arises from the stimulation of the centers of the vagus nerves. But then it turned out that m-cholinoblockers possess a similar property, which do not penetrate the blood-brain barrier. The agent "Atropin" is able to prevent bradycardia, which is caused by choline esters and AChE inhibitors, cardiac arrest during electrical stimulation of the vagus nerves.

Effect of the drug "Scopolamine" on the cardiovascular system

In small doses of 0.1-0.2 mg, the drug causes a significant reduction in the frequency of heart contractions. After an increase in dosage, a tachycardia is first observed, which occurs after half an hour, or a bradycardia replaces it. Already long ago the alkaloids of belladonna, as well as other m-holinoblokatory were prescribed for the treatment of parkinsonism. A higher result was achieved with their use in combination with the Levodopa drug. M-holinoblokatory find their application in extrapyramidal disorders , which are caused by neuroleptics.