Transient receptor potential channels in essential hypertension.
OBJECTIVE
The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated.


METHODS
We studied TRPCs in 51 patients with essential hypertension and 51 age-matched and sex-matched normotensive control subjects. Calcium and gadolinium influx into human monocytes was determined using the fluorescent dye technique. TRPC expression was measured using reverse transcriptase-polymerase chain reaction and in-cell western assay. Gene silencing by small interfering RNA for specific TRPC knockdown was also performed.


RESULTS
We observed an increased gadolinium/calcium-influx ratio through TRPC in essential hypertensive patients compared with normotensive control subjects [cation influx ratio (mean +/- SEM), 125 +/- 14 versus 80 +/- 7%; each n = 51; P < 0.01], due to an increase of gadolinium influx in hypertensive patients compared with normotensive control subjects (48 +/- 4 versus 36 +/- 3%; each n = 51; P < 0.05). We observed a significant increase of TRPC3 and TRPC5 protein expression in essential hypertensive patients compared with normotensive control subjects (normalized TRPC3 expression, 3.21 +/- 0.59 versus 1.36 +/- 0.07; each n = 20; P < 0.01; normalized TRPC5 expression, 2.10 +/- 0.28 versus 1.40 +/- 0.52; each n = 12; P < 0.05). We used small interfering RNA for knockdown of TRPC5. The thereby reduced channel expression caused a significant attenuation of calcium and gadolinium influx.


CONCLUSIONS
This study points to an important role of TRPCs in essential hypertension.
Liu
Daoyan
D
Med. Klinik IV, Nephrologie, Charité Campus Benjamin Franklin, Berlin, Germany.
Scholze
Alexandra
A
Zhu
Zhiming
Z
Krueger
Katharina
K
Thilo
Florian
F
Burkert
Antje
A
Streffer
Katrin
K
Holz
Stefan
S
Harteneck
Christian
C
Zidek
Walter
W
Tepel
Martin
M