Figure 1.

The myogenic response is greater in arterioles from diabetic (db/db) compared with non-diabetic (db/m) mice. (A and B) Representative recordings of vessel diameter in mesenteric arterioles from db/m and db/db mice with intact (A) or denuded (B) endothelium in response to step increases in intraluminal pressure from 20 to 120 mmHg at 5 min intervals. The active (vessel in Ca²⁺-containing PSS actively producing tone) and passive (Ca²⁺-free PSS) traces are shown in black and grey, respectively. (C and D) Summary data of myogenic constriction plotted as a function of intraluminal pressure in intact (C) and endothelium-denuded (D) vessels. For intact endothelium experiments, data represent the means ± SEM response of n = 5 vessels from 5 db/m animals (open circles) and n = 5 vessels from 4 db/db animals (filled circles), *P < 0.05; two-way ANOVA. For denuded endothelium experiments, data represent the means ± SEM response of n = 4 vessels from 4 db/m animals (open circles) and n = 5 vessels from 3 db/db animals (filled circles), *P < 0.05; two-way ANOVA.