Search

Copper(II) and nickel(II) complexes of macrocyclic polyamine derivatives possessing partial oligopeptide-like structures are found to suppress the xanthine-xanthine oxidase-mediated reduction of nitroblue tetrazolium and also to suppress formazan formation by potassium superoxide. The activity in the superoxide dismutase assay is dependent on ring size, type and number of donor atoms, metal ion, and substituents on the macrocycles. Some of those are more active than the known O2- scavengers such as copper(II)-salicylate and copper(II)-amino acid (or peptide) complexes. Nickel (II)-naphthylmethyl-dioxo-[16]ane N5, 13, 1:1 complex (NiH-2L) is the most active among the 30 chelates examined.

Changes of noradrenaline (NA) and prostaglandin (PG) E2 in gastric mucosa and gastric wall blood flow (GWBF) were investigated after stress load in rats with obstructive jaundice. We found that water immersion and restraint stress more easily increased the ulcer index and decreased GWBF, corresponding to a decrease of the NA and PGE2 contents in the gastric mucosa, as the duration of jaundice increased. Administration of PGE2 reduced the increase of the ulcer index and the decrease of the GWBF and NA contents in the gastric mucosa. It is suspected that the rapid decrease of NA and PGE2 is connected with the rapid decrease of GWBF after stress load in obstructive jaundice, and we reached the hypothesis that both PGE2 and NA mutually regulate local GWBF.