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The age-related dynamics of the activity of signalling pathways coupled to alpha1-adrenergic receptors and their dependence on the sympathetic innervation of arterial smooth muscle have been studied. The effects of the protein kinase C inhibitor (GF109203X, 10(-6) M) and the Rho-kinase inhibitor (Y27632, 10(-5) M) on the isometric contraction of the rat saphenous artery, induced by the alpha1-adrenoceptor agonist methoxamine, were examined. It was shown that the sensitivity to methoxamine of arteries from 2-week-old rats that are partially innervated was reduced as compared to adults, but the effects of both inhibitors were more prominent. The denervation induced by the excision of sympathetic ganglia increased the arterial sensitivity to methoxamine but was not accompanied by changes in sensitivity to the inhibitors. Therefore, the postnatal development of the arterial smooth muscle is characterized by a decrease in the contribution of protein kinase C and Rho-kinase to the regulation of contraction; however, these changes do not correlate with changes in the sensitivity of arteries to methoxamine and development of sympathetic innervation.

Unilateral ganglionsympathetectomy-removal of right upper cervical sympathetic ganglia and its combination with acute acoustic stress results in intensification of process of free radical oxidation of lipids and balance disturbance between components of antioxidative and pro-oxidative system of blood. Changes of composition and activity Cu, Zn-superoxide dismutase, catalase activity and contents of catalase, ceruloplasmin, transferrin and metalloproteins pro-oxidative action such as (cytochromes b558(I), b558(II), b558(III), b558(IV)) as well as O2-producing lipoprotein suprol and cytochromes b5 are evidence of compensating-adoptive function disturbances with according changes in blood, relatively to adaptive-trophic function of sympathetic system, its regulative role, in system of tissue metabolic conversion, which is directed, in particular, on compensation of anti-radical protection of cells.

An examination of 41 patients within the period from 6 to 21 years after operation on the sympathoadrenal system for progressing hypertonic disease has shown a stable hypertensive effect of operative interventions even in the group of patients with the 3rd degree of the disease, which allows to recommend including them in the complex of measures for correction of arterial hypertension resistant to pharmacotherapy.

Under study was the influence of the nerve growth factor on morpho-functional and cytometrical characteristics of sympathetic neurons after cutting their axons. The work was carried out in albino rats which were subjected to dissection of the external and internal carotid nerves of the cranial cervical ganglion. This operation resulted in death of about 50% of the neurons of the node in question, in 30 and 60% in reduction of the intensity of fluorescence of the neuron body catecholamines within 7 and 14 days. The cause of these changes might be the cessation of entrance of the nerve growth factor from target tissues by means of retrograde transport. After 6-10 exogenous administrations of the latter (10-20 mkg/g of the body weight) 14 days after operation the amount of neurons in the cranial cervical ganglion did not practically differ from that in the group of intact rats. Seven and fourteen days later specific luminescence of the neuron body catecholamines was 24-22% greater than the values found in the operated animals given the isotonic solution of sodium chloride. Parallel stimulation of the formation of a powerful network of collateral branches by injured axons was performed resulting in more considerable (3-fold) increase of the ganglion mass than in the operated animals (2-fold) not treated with a neuro-growth protein. The newly formed fibers had not only an intercellular but also subcapsular arrangement which spoke of higher reparative--regenerative potencies of the neuron.

The nucleus and soma of sympathetically denervated smooth muscle cells (SMCs) of the cat nictitating membrane were found to be enlarged. The number of free ribosomes was dramatically increased and a disintegration of microfilaments was found. The functional changes involved spontaneous or agonist-induced generation of APs. These findings suggest that the denervation destructed the adrenoreceptor control mechanisms of the excitable membrane's potential. The possibility of emergence of new Ca2+ channels in the denervated SMCs is discussed.

The reorganization of forced swimming time-course and behaviour in open field after superior cervical ganglionectomy in rats may be the result of disorders in adaptive processes. Behavioral shifts seem to be induced by the denervation of pineal gland with its adaptive properties. An increase of antidepressant drug (amitriptyline) activity was observed in both tests.

Lumbar sympathectomy in patients with obliterating atherosclerosis of lower extremities in the nearest postoperative period results in acceleration of the intracutaneous blood flow and of intramuscular blood flow as well as in greater extra-tissue blood shunting. At remote terms the intramuscular bloodflow is also accelerated. Patients with the IV degree of ischemia should be divided into two groups according to results of special investigations: patients with traumatic and with ischemic necroses. It is of importance for choice of rational surgical methods and for prognosis of outcomes of the disease.

The experiments in dogs suggested an essential difference in terms of the rearrangement of regional blood circulation in the skin and muscles of the extremity after experimental sympathectomy. Ganglionectomy induced a reduction of general peripheral arterial resistance on the operated side, an increase in the skin tissue blood flow and its oxygenation rate, a deceleration of the process of biological oxidation reducing the capability of muscles to use blood oxygen and cutting down the maximum of oxidase cytochrome (a3) activity. There was no essential change in the regional acid-alkaline balance. The above changes were due to a disturbance of the neurotrophic sympathetic effect on tissues.