TONIC AND STIMULUS-DEPENDENT CONDUCTION OF EXCITATION BLOCKING IN THE NERVE BY MEANS OF ANTIARYTHMISANT PENTILAYMALIN
The problem of anesthesia is traditionally very urgent in neurophysiology and medicine. Local anesthesia is an important component of the general anesthetization. In spite of the wide variety of local anesthetics, the necessity to search for and study new substances, which possess local anesthetic activity, is still an urgent objective of the modern physiology and medicine. Local anesthetics differ according to the speed of the blocking effect and its duration. During anesthesia they are usually injected into the area of nerve trunks. That is why the information on the dynamics of excitation blocking in fibers of the nerve trunk is very interesting. Research methods. Scientific-methodical literature analysis and summarizing, experiment, statistical data manipulation. Materials. It is known that antiarythmical preparations, as the local anesthetics, block Na <sup>+</sup>- channels. That is why the research works, directed at antiarythmical preparations use as local anesthetics are very urgent. There is tonic blocking of excitation conduction on nerve fibers, which leads to the gradual amplitude decrease of action potentials under the influence of Na <sup>+</sup>- channels blockers and a stimulus-dependent blocking, which leads to action potentials generation inhibition and their full suppression during the process of a rhythmic nerve stimulation. Stimulus dependency - a phenomenon used in clinical pharmacology. The effectiveness of medicinal substances is shown, which increase a stimulus-dependent blocking of natrium channels, in order to eliminate neuropathic pain, arrhythmia, pain in case of cancer. Pentilaymalin is an antiarythmic of an ajmaline row and its anaesthetic characteristics are not studied. Results. In experiments with the sciatic nerve of the lacustrine frog it is shown, that an antiarythmic pentilaymalin causes the decrease of the maximum amplitude of an action potential of nerve to 50% from the initial value within 120 minutes. An amplitude renewal of the nerve action potential in case of further holding in Ringer solution happens during 39,5 hours. A stimulusdependent block under the influence of the pentilaymalin develops within milliseconds. Conclusion. The results of the experiment showed, that antiarythmic pentilaymalin is an anaesthetic of the prolonged effect. The mechanism of the pentilaymalin action is conditioned by its interaction with natrium channels. In case of a nerve electric stimulation pentilaymalin causes strong stimulus-dependent blocking of nerve fibers.