Premium
Potential Role of TRPC1 and TRPP2 Channels in Mediating Calcium Signaling Response of Brain Microvessel Endothelial Cells to Mechanically‐Induced Injury
Author(s) -
Berrout Jonathan,
Jin Min,
O'Neil Roger G
Publication year - 2010
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.24.1_supplement.1033.9
Subject(s) - trpc , trpc1 , transient receptor potential channel , microvessel , microbiology and biotechnology , chemistry , endothelial stem cell , trpc3 , intracellular , calcium in biology , voltage dependent calcium channel , calcium , medicine , biology , biochemistry , receptor , angiogenesis , organic chemistry , in vitro
Traumatic brain injury can lead to the breakdown of the blood brain barrier (BBB). Since elevation of cytosolic calcium levels, [Ca]i, can compromise the BBB integrity, we assessed the effects of mechanical injury on [Ca]i in brain endothelial cells. Mouse brain microvessel endothelial cells (bEnd3) were grown on elasticized membranes and [Ca]i monitored using Fura 2 fluorescence imaging. Application of a “moderate” injury, using a pressure/stretch pulse of 50 ms (~35% stretch; Cell Injury Controller II module), induced a rapid transient increase in [Ca]i by 129 +/− 27 nM. In the absence of extracellular Ca, the injury‐induced [Ca]i transient was greatly reduced, but not eliminated, implicating both Ca release from intracellular stores and Ca influx across the cell membrane. Unloading of Ca stores by treatment with thapsagargin (10uM) did not abolish the injury transient. Addition of LOE‐908 (10uM) and Amiloride (10uM), TRPC and TRPP2 channel blockers respectively, both reduce the transient [Ca]i increase. In addition, siRNA knockdown assays have implicated the involvement of TRPC1 and TRPP2 in mediating the injury‐induced [Ca]i response. It is concluded that mechanical injury of brain endothelial cells induces calcium influx, implicating [Ca]i transients in injury‐induced barrier breakdown. Further, the induced Ca influx appears to be associated with injury‐induced TRPC1 and TRPP2 channel activation.