Raw data for the article: Role of oxidative/nitrosative stress in dysfunction of rat’s intracerebral parenchymal arterioles in low sodium environment in the presence of vasopressin

All studies were performed on isolated rat’s intracerebral small vessels − parenchymal arterioles in low sodium environment in the presence of vasopressin, which mimics AVP-associated hyponatremia in vivo. The purpose of the present study was to investigate the mechanism of dysfunction, that is, constriction and impaired endothelial regulation of parenchymal arterioles in conditions of decreased Na⁺ concentration to 121 mM and increased AVP concentration to 15pg/ml. Raw data show percentage changes in parenchymal arteriole diameter (referred to Figures 2-7), which explain the mechanisms of vascular dysfunction in a low sodium and elevated vasopressin environment. Raw data for Figure 8 show detection of superoxide anion in isolated parenchymal vessels.The results of these studies demonstrated that the dysfunction of small vessels in these conditions is associated with 1) decreased involvement of NO in maintaining the basal tone of parenchymal arterioles, 2) involvement of oxidative/nitrosative stress, activation of V_1a and ET_A/ET_B receptors. Metabolites of arachidonic acid, such as CYP450 4A-derived 20-HETE and COX-derived TXA_2, were not involved in the studied mechanisms. Administration of NO precursor, L-arginine, likewise did not improve vascular disorders observed in low sodium environment in the presence of vasopressin. The present studies revealed also increased superoxide formation in such conditions.