The dissertation is devoted to the study of complex clinic-instrumental and biochemical change in participants of liquidation of consequences of emergency on ChNS with cerebro-vascular disorders. For carrying out of the research - the spektrophotometrical method of Tsanev and Markov and modified micromethods of Levitsky and Samoiliuk, EEG, RVG, KT, imunograms were used. The investigation of nuclein metabolism were carried out in patients with multiple sclerosis, stroke, tumors, arakhnoiditis and liquidators with cerebro-vascular disorders. In hemoragic stroke patients observed is - the increase of DNA and RNA content, and of all ferments activity (DNA-s I, DNA-s II, RNA-s I, RNA-s II) in peripheral blood. In ishemic stroke - takes place the increase of nucleic acids content and of nucleas activity. For tumours of any genesis characteristic is the increase of DNA content and RNA content - and the increase of activity of DNA-s I, RNA-s II, and lowering of activity of DNA-s II simultaneously. In arakhnoi dits - there also takes place the increase of DNA and RNA content and of activity DNA-s I, RNA-s II, at the same time - the activity DNA-s II - is lowered. In patients with multiple sclerosis take place other changes in ideces of nuclein metabolism. So, DNA content in peropheral blood of patients - is increased, comparing to control, and RNA content - is decreased. Nucleases activity also differs, namely: observed is the lowering of DNA-s I and DNA-s II activity , and at the same time - RNA-s I, RNA-s II activity - increases.The lowering DNA and RNA and increase of nucleases activity (DNA-s I and RNA-s I) in peripheral blood of patients with CVD - testify to the presence of destructive processes in nervous system of liquidators.The depression of T-helpers and increasing of Ig A Ig G and CIK in patients with CVD - testifies to the depression of immune system function.Analysis of the obtained data permits us to deepen knowledge about pathogenesis CVD in liquidators.