AA diameter responses to ANG II (0.1, 1, 10 nM) in kidneys of db/m and db/db mice. Kidneys from db/m and db/db mice were incubated in euglycemic (NG, 5 mM glucose) and hyperglycemic (HG, 30 mM glucose) perfusion and superfusion solutions. A and C: AA diameter (μm, A; Δ% of control, C) responses to increasing doses of ANG II for db/m-NG (n = 12) and db/m-HG (n = 13) kidneys. B and D: AA diameter (μm, B; Δ% of control, D) responses to increasing doses of ANG II for db/db-NG (n = 16) and db/db-HG (n = 12) kidneys. AA from db/m-NG, db/m-HG and db/db-NG, db/db-HG responded to increases in ANG II with a significant reduction in diameter. The magnitude of the AA vasoconstrictor responses was not significantly different between db/m-NG and db/db-NG kidneys or between db/db-NG and db/db-HG kidneys. Data are means ± SE. *P < 0.05 vs. baseline diameter; †P < 0.05 db/m-NG vs. db/m-HG.