Cholinesterase inhibitors: pharmacological application
As you know, in the nervous system there are manysynapses. They are necessary for the transmission of impulses. In this process, several types of mediators are involved. Among them - acetylcholine, norepinephrine, GABA, serotonin, etc. Mediators (transmitters) are necessary for signaling between neurons. In addition, thanks to them, excitation or inhibition of the musculature is carried out. With various pathologies of the nervous system, the work of neurotransmitters can be disrupted. This happens due to atrophic and degenerative processes in the brain. In these cases, drugs are used to amplify or reduce signal transmission. Such a pharmacological group includes cholinesterase inhibitors. They are used for myasthenia gravis, neuritis, amyotrophic sclerosis, Alzheimer's disease, mental pathologies.
Effect of cholinesterase inhibitors
Cholinesterase inhibitors are medicaldrugs that are widely used in neurology and psychiatry. They are divided into several groups, each of which is applied in a particular case. The action of these medicines is based on blocking cholinesterase. This enzyme is available both in healthy people and in those suffering from various diseases. It is necessary for the cleavage of the neurotransmitter - acetylcholine. As a result of its action, the transmitter breaks down to choline and acetic acid. With various pathologies of the brain there is a gradual atrophy of the cortex. As a result, some structures can completely collapse, including the cholinergic system. In addition to brain atrophy, degenerative processes of autoimmune, infectious, viral nature lead to this. Due to the destruction of the forebrain nuclei, there is a pronounced lack of a neurotransmitter, acetylcholine. To ensure that there is no shortage of this substance for as long as possible, it is necessary to work on the enzyme that destroys it. For this purpose, cholinesterase inhibitors are used. Thanks to them, the activity of the neurotransmitter can persist for several years.
Cholinesterase inhibitors: classification of drugs
There are several types of anticholinesterasepreparations. They are classified according to the pharmacological effects on the enzyme. Some of them block cholinesterase irreversibly, others - temporarily. There are 3 groups of medicines. Among them:
- Reversible blockers. These cholinesterase inhibitors act on the postsynaptic signaling. Thanks to them, the action of the enzyme is temporarily interrupted. To this group include acridines and piperedany.
- Pseudo-invertible cholinesterase blockers. The mechanism of their action is in connection with the onion part of the enzyme molecule. In addition, they are able to bind to acetylcholine receptors. Similar properties have a group of carbamates.
- Irreversible inhibitors of cholinesterase. Preparations of this group are called organophosphorus. Representative is the drug "Metrrionat".
To the group of acridines are preparations "Tacril" and "Velnacrin". Representatives of carbamates - medicines "Rivastigmine", "Epistagmine."
Indications for the use of cholinesterase inhibitors
Cholinesterase inhibitors are used to treatmuscular diseases of the central genesis, atrophic and degenerative pathologies of the brain. In addition, some medicines are available in the form of drops. They are used for increased intraocular pressure - glaucoma. Drugs that inhibit cholinesterase reversibly are prescribed for the treatment of dementia, Pick's disease and Alzheimer's. Preference should be given to the group of piercedans, as they act selectively and have fewer side effects. Recently, indications for the use of medicines have expanded. This is due to a more detailed study of their properties. To diseases in which prescribe anticholinesterase drugs, include myasthenia, intestinal atony, muscular dystrophy, amyotrophic lateral sclerosis, paralysis of limbs of degenerative origin. Irreversible inhibitors are used for poisoning.
Contraindications to the use of anticholinesterase drugs
Medications related to this group are notapply in convulsive syndrome, hyperkinesia of any etiology. They are also contraindicated for patients suffering from severe heart failure, bronchial asthma, thyrotoxicosis. It is undesirable to take anticholinesterase drugs with concomitant stomach ulcer, enteritis. Medicines are not shown to pregnant and lactating women.
Cholinesterase inhibitors: drugs of choice in Alzheimer's disease
Alzheimer's disease is an atrophic lesionCNS, in which there is amnesia, personality disorder and dementia. Scientists around the world are trying to find a cure for this pathology. With mild and moderate disease, the drug of choice is Donepezil. It refers to reversible inhibitors of cholinesterase, has a selective effect. The medication is used for the purpose of pathogenetic therapy. He is unable to completely cure the patient, but slows down the development of Alzheimer's symptoms.
