STRYCHNINE (Strychninum) — stimulator of the central nervous system; main alkaloid of seeds to a nuxvomica (Strychnos nux vomica) and nek-ry other plants this. loganiyevy (Loganiaceae), growing in the tropical districts of Africa and Asia. On a chemical structure is derivative indole (see).
In medical practice use strychnine nitrate (Strychnini nitras; synonym of Strychninum nitricum; GFH, joint venture. A); With 21 H 22 N 2 O 2 - HNO 3 :
Colourless brilliant acicular crystals or white crystal powder. Let's difficult dissolve in water (1:90) and alcohol, we will easily dissolve in a boiling water (1:5), it is practically not ether-soluble; pier. weight (weight) 397,43. Water solutions have neutral or subacidic reaction. They will be sterilized at £ °100 ° within 30 min.; 0,1% solution of strychnine of nitrate in ampoules is acidified (0,1 N by solution salt to - you) and has pH 3,0 — 3,7.
Exerts the stimulating impact on back and to a lesser extent on a brain. Increases reflex irritability of the segmented device and already in small doses raises it so that even weak irritations cause generalized motor reaction. Along with it the tone of smooth muscles of internals (a stomach, intestines, a bladder) raises. Exciting the respiratory and vasomotor centers, S. increases amplitude and frequency of respiratory movements, raises the ABP. These effects are especially expressed against the background of preliminary oppression of the bulbar centers. The page strengthens also function of analyzers (increases visual acuity and broadens the field of vision, aggravates hearing, sense of smell, taste). Changes of sight are connected not only with S.'s influence on the central components of the visual analyzer, but also with direct impact on a retina.
Exciting action on c. the N of page depends on not selective activation first of all of spinal internuncial neurons and disturbance of processes of postsynaptic braking. The page specifically interacts with brake postsynaptic receptors, lowering their sensitivity to a brake mediator to glycine (see). Explain with excitement of internuncial neurons and weakening of postsynaptic braking simplification of generalization of reflex answers under the influence of S. V toxic doses of S. perverts reaction of brake receptors to glycine that leads to generation of exciting potentials instead of brake.
The page is easily soaked up through mucous membranes. In an organism a considerable part of the administered drug collapses in a liver and only apprx. 20% in not changed look is removed it by kidneys. Full allocation happens within 3 — 4 days owing to what at repeated reception of S. its cumulation is possible.
Due to the small width of therapeutic action S.'s use is very limited. It is used by hl. obr. for treatment of paresis and paralyzes in the recovery period, during the weakening of breath and cordial activity as a result of intoxication, at nek-ry functional vision disorders (an amblyopia, an amaurosis), an atony of a stomach and intestines.
Appoint inside and under skin in the form of 0,1% of solution, the adult inside on 0,0005 — 0,001 g 2 — 3 times a day, to children are more senior than 2 years — on 0,0001 — 0,0005 g on reception depending on age. To children up to 2 years S. is not appointed.
The highest doses for adults inside and under skin: one-time 0,002 g, daily 0,005 g.
In pilot studies of S. use for the analysis of relationship of neurons and separate structures of a brain among themselves (a method of a so-called strikhninny neyronografiya).
Toxic effekthe t is shown by tetanic spasms. Dominance of a tone of extensive muscles causes a pulling of extremities and, a flexure of a trunk with a zaprokidyvaniye of the head (opisthotonos). Spasms arise under the influence of external irritations. In an experiment they remain at dekapitirovantsy animals and disappear only after destruction of a spinal cord. Death at S.'s poisoning is caused by a spasm of respiratory muscles with the subsequent asphyxia. Treatment of poisoning includes the maximum barrier of the patient from external irritants, a gastric lavage, purpose of salt laxatives and carrying out an artificial diuresis (see. Poisonings ). At spasms give a radio and oxygen anesthesia, appoint tranquilizers of a benzodiazepine row, napr, diazepam, carry out artificial hardware respiration.
Use of Page. contraindicated at a hypertension, bronchial asthma, tendency to spasms, pregnancy, nephrite, hepatitis.
Forms of release: powder, ampoules on 1 ml of 0,1% of solution. Powder is kept in well corked banks.
Except strychnine of nitrate, in medical practice use also containing Pages. drugs to a nuxvomica (see. Medicinal plants ), to the Crimea belong extract to a nuxvomica dry and tincture to a nuxvomica.
Tincture to a nuxvomica (Tinctura Strychni; synonym of Tinctura nucis vomicae; GFH, joint venture. B) — transparent liquid of brown color, bitter taste. Contains apprx. 0,25% of strychnine and brucine.
Apply as all-tonic and in quality bitterness (see).
Appoint inside the adult 3 — 10 drops to reception. To children 2 years are more senior appoint 1 — 3 drop to reception depending on age.
Extract to a nuxvomica dry (Extractum Strychni siccum; synonym of Extractum nucis vomicae siccum; joint venture. A) — dry powder of inodorous light-brown color. Contains apprx. 16% of strychnine and brucine.
Indications to appointment same, as at use of strychnine of nitrate (see above). Appoint inside the adult 0,005 — 0,01 g to reception.
The highest doses for adults inside: one-time 0,01 g, daily 0,03 g
See also Alkaloids .
Strychnine in the medicolegal relation
S.'s Poisonings are rather rare. Lethal doses of S. at intake for adult 0,1 — 0,3 g, for children of 0,005 g.
The conclusion about S.'s poisoning as about a cause of death put on the basis of set a wedge, manifestations, results court. - medical and laboratory researches. At necropsy find a venous plethora of internals, an anemia of skeletal muscles, dot hemorrhages in a soft meninx and a mucous membrane of a stomach. Sometimes in contents of a stomach find crystals of salts C. At court. - a chemical research C. take from biol. material also carry out by the acidified alcohol or water reaction with potassium bichromate in the concentrated chamois to - those. In the presence of S. blue-violet coloring is observed. Besides, S.'s maintenance in biol. material establish biol. by method (on frogs). Quantitative definition of S. is carried out in the colorimetric way (see Colorimetry), using Malaken's reaction — De-below based on S.'s recovery by hydrogen ions at the time of allocation and further oxidation of a product sodium nitrate. During this reaction there comes red coloring. Besides, quantitatively S. determine by method of paper chromatography (see the Chromatography).
The page a long time remains in a corpse that causes high informational content court. - chemical researches even of the decayed corpse.
Bibliography: Avdeev M. I. Course of forensic medicine, page 394, M., 1959; And r at-sh and N I am E. B N. Influence of strychnine and other konvulsant on processes of the central tormosheniye, Pharm. and toksikol., t. 32, No. 2, page 236, 1969, bibliogr.; 3 and to a mustache about in V. V. Pharmakologiya of the central synapses, M., 1973; The Guide to forensic medical examination of poisonings, under the editorship of R. V. Berezhny, etc., M., 1980; Forensic medicine, under the editorship of V. M. Smolyaninov, page 251, M., 1975; Antiepileptic drugs, mechanism of action, ed. by G. H. Glaser a. o., p. 249, N. Y., 1980.
E. B. Arushanyan; I. V. Buromsky (court.).