FIGURE 3.
The UTP-mediated vasoconstrictions are insensitive cholesterol depletion. Representative immunoblots from sucrose gradients and their quantification show that perfusion of HCA with Krebs Ringer buffer containing 10 mm MβCD for 1.5 h caused a 60% reduction in the P2Y2R recovered in raft fractions (A and B). C shows representative tracings of the vasomotor activity elicited by HCA rings prior to and following treatment with MβCD. Cholesterol depletion by MβCD did not modify either 1 μm UTP- or 70 mm KCl-evoked vasomotor responses but substantially decreased vasoconstrictions induced by 100 nm 2-MeSADP. D shows a quantification of these responses. Columns, mean values; bars, S.E. (n = 3–4 per assay). *, p < 0.05 when comparing the effect of UTP in tissues with and without MβCD treatment.