Figure 2.

(a) Changes in endothelial cell tubule formation following incubation with sera from heat therapy (with and without 1mM Nω-nitro-L-arginine [L-NNA]) and sham subjects collected before (0 wk) and 1 h after (Acute HT) the first hot water immersion session and following heat therapy (8 wk). Endothelial tubule formation was significantly improved following exposure to sera from subjects in the heat therapy group following acute and chronic hot water immersion. No other significant changes were observed. Data are mean±SE, *p < 0.05. (b) Representative phase contrasted images at 2.5X magnification of endothelial cells exposed to sera collected from the same subject in the heat therapy group before and after 8 wk of heat therapy, with and without L-NNA, and from a subject in the sham group (all pre-water immersion).