Affiliation: | 1. Department of Cell Biology, Calabria University, Rende (CS), Italy A. Martini and R. Bruno contributed equally to this work.;2. Department of Pharmaco-Biology, Calabria University, Rende (CS), Italy A. Martini and R. Bruno contributed equally to this work.;3. Department of Cell Biology, Calabria University, Rende (CS), Italy |
Abstract: | Aim: The T-type calcium channel is expressed in vascular endothelial cells, but its role in endothelial cell function is yet to be elucidated. We analysed the endothelial functional role of T-type calcium channel-dependent calcium under angiotensin II (Ang II) stimulation. Methods: Human umbilical vein endothelial cells were co-incubated with hormone at 10−7 m and either Efonidipine 10−5 m or Verapamil 10−5 m or Mibefradil 10−5 m or Wortmannin 10−6 m . The contribution of Ang II receptors was evaluated using PD123319 10−7 m and ZD 7155 10−7 m . The calcium ion concentration was observed using Fluo-3 acetossimetil ester. The cells were observed after 3, 6, 9 and 12 h. Results: The microfluorescence method points out that Ang II induces intracellular calcium modulation in time by distinct mechanisms. AT2 receptor blockade is necessary to observe significant increase in [Ca2+]i levels. Pre-treatment with Mibefradil abolishes Ang II -induced cell migration. Conclusions: Our data show that Ang II, via AT1 receptor, modulates calcium concentration involving T-type calcium channel and L-type calcium channel but only the calcium influx via T-type calcium channels regulates endothelial cell migration which is essential for angiogenesis. |