Abstract 19372: Role of TRP Channels in Mechanical Stimulation Responses of Coronary Pericytes
Pericytes are contractile cells which have been implicated in control of the microcirculation. It is not clear, however, if pericytes sense mechanical forces, and which mechanisms are involved. We performed global gene expression analysis using RNAseq in primary cultured myocardial pericytes, and found multiple mechanosensor candidates previously demonstrated to mediate mechanotransduction in vascular smooth muscle cells, including transient receptor potential (TRP) channels TRPM4 and TRPM7. In vascular smooth muscle cells, TRP channels have been implicated in the regulation of vascular tone. Therefore, we hypothesized that TRP channels play a role in the pericyte response to mechanical stimulation. Using qPCR and immunoblotting, we further confirmed expression in these cells. Immunocytochemistry of TRPM7 revealed membrane localization, while TRPM4 showed predominantly perinuclear localization. To simulate mechanical stimulation by compressive force, weight (1g/cm2) was placed atop glass coverslip-covered cells and cellular responses were monitored by live-cell imaging. Weight application induced a significant calcium response (n = 20), which was reduced by pre-treatment with a nonspecific pharmacological inhibitor of TRPM7 (2-aminoethoxydiphenyl borate (2-APB), 100uM, n = 17, p < 0.01). These data suggest that TRPM7 is involved in the pericyte response to mechanical stimulation, potentially providing insight into the mechanisms by which pericytes contract in the coronary microcirculation.
Author Disclosures: E. Cilento: None. Z. Cao: None. J. Iliff: None. N. Alkayed: None. S. Kaul: None.
- © 2016 by American Heart Association, Inc.