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Aim: To investigate the action of anions and anion channel blockers in the regulation of vascular contraction induced by norepinephrine (NE)., Methods: NE-induced contraction was observed in rat aorta by using routine blood vascular perfusion in vitro., Results: The anion channel blockers niflumic acid (NFA) and 5-nitro-2-(3-phenoxylpropylamino)-benzoic acid (NPPB) produced inhibitory effects on NE-evoked contractions in the aorta. NE-induced contraction was not significantly changed after the extracellular Na+ was replaced by choline, in contrast, the vascular was relaxed when the extracellular Cl- was replaced by glutamate. Moreover, the vasoconstriction induced by NE was further enhanced with the replacement of the extracellular Cl- by Br-, which was still sensitive to either NFA or NPPB., Conclusions: Anion channels play an important role in the regulation of blood vascular tone, which may be responsible for the salt-sensitivity hypertension.

The anion transport property is the one of the most important functions of the erythrocyte. In this paper a new method is used to measure the NO2- and Cl- ions transport across the erythrocyte membrane in burned rats. It was found that the NO2- and Cl- transport rate across erythrocyte membrane became slower during shock stage in burned rats, being contrary to the results found in heat-treated erythrocytes in vitro. By using a specific inhibitor of anion transport, DIDS, it was shown that the abnormality of NO2- transport across the erythrocyte membrane in burned rats is due probably to a damage of extracellular domain of band 3 protein. The authors consider that the influence of membranotoxic factors and the disturbance of energy metabolism during burn shock stage are accounted for all the noticed alterations.

The status of negative charge on RBC and glomeruli and its relation to proteinuria of adriamycin nephrosis in rats were studied by electron computerized picture analysis. The results showed that the negative charge (NC) on glomeruli decreased significantly at 48 hrs and 14 days after ADR injection although there was no proteinuria simultaneously. There was a positive relation between the changes of NC on glomeruli and those on RBC (r = 0.77, p less than 0.01), and there was negative relation between either of them and proteinuria respectively (r = -0.5140, p less than 0.05; r = -0.5231, p less than 0.01). The focal fusions of foot processes occurred prior to the onset of proteinuria.