In conditions of acute experience was studied influence of the endothelium on the speaker of mechanical characteristics of the a. carotis communis sinistra of rabbit (n = 16), during cardiac cycle. Is detected, that the change of the diameter of artery was not synchronous with the change of intravascular pressure and depends at the phase of cardiac cycle. The conducted account of an elastic modulus for components of a wall of an artery has shown, that the degree of activity of a smooth musculation of the arterial wall is various with the phase of pulse wave of intravessels pressure and depends from intact of the endothelium. Is exhibited, that the endothelium rendering anticonstriction effect at a smooth musculation of arteries, promotes optimisation of trunk functions of arteries and stabilisation peripheral blood flow.