Venous vasodilators
This information is not intended for purposes of treatment without physician.
Description of the pharmacological group
The medicines, which predominantly reduce the tone of venous vessels, the venous vasodilators
For many years the nitroglycerine successfully used for stopping the assaults of stenocardia (sin.: angina pectoris, the Gebert disease).
At present in the wide clinical practice besides the nitroglycerine (isolitterbiyes trinitrate) use of analogous to it by the mechanism actions other organic nitrates - isolitterbiyes mono-nitrate and dinitrate, and also not relating to nitrates according to the chemical structure, but close to them in the mechanism of the action of sydnonimyn (molsidomin and other).
Nitrates possess the sufficiently wide spectrum of pharmacological action, but the smooth musculature of vessels is the fixed points of the application of their effect.
At the end 20 century in the endothelium of vessels was revealed the endogenous biologically active substance, which was called name endothelial relaxing factor (Endothelium-derived of relating of factor - EDRT). The endothelial relaxing factor (ERF) similar to organic nitrates causes the weakening of vascular wall and suppresses the aggregation of thrombocytes. It was more lately explained that according to the chemical structure ERF it is the oxide of nitrogen (NO).
Thus, organic nitrates can be considered as the exogenous donors of natural biologically active substance - the oxide of nitrogen, i.e., of ERF.
As it was noted, nitroglycerine was inculcated by the first of organic nitrates into the clinical practice. At the end 1940's in England was synthesized and inculcated in the clinical practice isosorbide dinitrate, and then its natural metabolite - isolitterbiyes mono-nitrate.
At present in the clinical practice various medicinal forms of all three representatives of the class of organic nitrates widely are used.
The medicines, which relate to the group of organic nitrates, classify as follows.
The I. organic nitrates of high frequency action for stopping the assaults of stenocardia.
1. Group of nitroglycerine - the tablet of nitroglycerine, spray of nitrolingual and others
2. Group isolitterbiyes of dinitrate - isosalmon of spray.
the II. Organic nitrates of short action.
1. Group isolitterbiyes of dinitrate - from poppy 5 mg, nitrosorbid and other
2. Group isolitterbiyes of mono-nitrate - mono poppy, effox and other
the III. Prolonged medicinal forms of organic nitrates.
1. Group of nitroglycerine - sustac, nitron, trinitrolong, ointment nitro 2%, TTS of nitroderm and others
2. The group isolitterbiyes of dinitrate - isosalmon of retard, kardiket and other
3. Group isolitterbiyes of mono-nitrate - olicard retard, effox long and other
IV. Medicinal forms of organic nitrates for the intravenous introduction.
1. The group of nitroglycerine - perlinganit and other
2. The group isolitterbiyes of dinitrate - isosalmon for the infusion and other medicinal forms of organic nitrates of high frequency action are intended only for stopping the assaults of stenocardia. As a rule, organic nitrates of high frequency action assume under the language, for example tablet either the capsules of nitroglycerine or they use in the form dosed aerosols, for example the isosalmon of spray. Effect from the application of these medicinal forms of organic nitrates is developed by the rapidly- in 1 -3 min, but has short-term nature; therefore this group of organic nitrates for the preventive maintenance of assaults stenocardia does not use.
The action of organic nitrates of short action begins in 15- 20 min and continues depending on medicinal form from 2 to 6 h. thus, for instance, the action of preparation from poppy 5 begins after 3-4 min, it reaches maximum to the 15th minute and continues during 45-120 min. this medicinal form of organic nitrates uses for warning the assaults of stenocardia (for example, before the output to the street). Another preparation from this group ( nitrosorbid ) comes into action 15 min after method, maximum effect is developed on the average to 30 60- y to minute, and the action of preparation continues on the average of approximately four hours.
These medicines use for the preventive maintenance of the assaults of stenocardia. However, for the preventive maintenance of assaults most frequently use various prolonged medicinal forms of organic nitrates, whose action begins in 20- 30 min and continues depending on medicinal form it is eighth 24 h. majorities of them assume per os, for example, sustac, nitrong, effox long so forth
Are at the same time in the clinical practice inculcated other medicinal forms of prolonged organic nitrates: buccal (from Lat. bucca - cheek), i.e., stuck on the cheek or the gum medicinal forms, for example trinitrolong; trans-dermal (from Lat. trans - through; Greek. derma - skin) the systems, which are plates with the nitroglycerine, for example TTS of nitroderm; ointment with the nitroglycerine, for example nitro 2% ointments.
Beginning with 1980`s years in the clinical practice widely use the medicinal forms of organic nitrates for the intravenous introduction - preparations it perlinganit, isosalmon for the infusion and these other medicinal forms are used in the complex therapy of sharp myocardial infarction, and also for the controlled hypotonia.
To the side effects of organic nitrates should be carried the reflector tachycardia, caused by a decrease in arterial pressure, and also the headache. The headache against the background of the method of organic nitrates are connected with the fact that they in the larger measure they enlarge the surface, than deep vessels of brain. This entails the development of the syndrome of robbing the tissues of brain and, therefore, their functional hypoxia.
With the designation of organic nitrates one should consider the fact that to them sufficiently rapidly it is developed tolerance. They assume that at the basis of the development of tolerance lies reduction in the reserve of sulfhydryl groups (SH) in the endothelium of vessels.
By the mechanism of action to organic nitrates is close the preparation of molsidomin (sin.: korvaton), which although differs from them in the chemical structure, is also the donor of the oxide of nitrogen (N0). Preparation enlarges venous vessels and thus reduces preload to the myocardium, it enlarges large epicardial coronary arteries, improves collateral blood circulation and reduces the aggregative ability of thrombocytes, which in the final analysis leads to the decrease of the need of heart for oxygen and an improvement in the functional state of the focus of ischemia of myocardium.
In the clinical practice of molsidomin uses for the averting, and in certain cases also stopping the assaults of stenocardia.
Venous vasodilators are used to treat diseases of the vessels of the brain and peripheral vessels