Detection of TRPV4 channel current‐like activity in Fawn Hooded Hypertensive (FHH) rat cerebral arterial muscle

Abstract

The FHH rat strain is associated impaired pressure‐dependent myogenic tone and exaggerated cerebral arterial muscle KCa channel current opening. In the present study we examined if the FHH rat cerebral arterial muscle cells exhibit TRPV4 channel current‐like activity. Western blot analysis and RT‐PCR revealed expression of protein and transcript for TRPV4 channel in cerebral arteries of FHH rat strain. Immunostaining using the TRPV4 channel antibody detected presence of TRPV4 channel protein in freshly isolated FHH rat cerebral arterial myocytes. Patch clamp recording of single‐channel current activity in FHH rat cerebral arterial myocytes identified presence of a non‐selective cation channel current with unitary conductances of ~96 pS and ~84.6 pS at depolarizing and hyperpolarizing potentials, respectively, that were sensitive to inhibition by the TRPV4 channel inhibitor RT‐1734 (5 μM) or HC 067074 (0.2 μM) and activated by the potent TRPV4 channel agonist GSK‐101690A (100 nM). These findings indicate that the FHH rat cerebral arterial myocytes appear to express TRPV4 channel current‐like activity that could have relevance for the regulation of calcium movement and calcium‐dependent mechanisms in these cells.Support or Funding InformationThis work is supported by grants from NIH (R01 NIH/NHLBI, HL033833 and HL105997)