[Aldosterone stimulates hepatic stellate cells contraction via Ca2+-independent pathways]

To investigate the mechanisms of Aldosterone stimulating hepatic stellate cells(HSCs) contraction via Ca2+-independent pathways.

HSC-T6 cell line was pre-disposed with Aldo 10mumol/L. The cell contraction was detected by silicone-rubber-membrane cultivation directly. The concentration variation of intracellular free calcium in rat HSC was observed by laser confocal microscopy. Besides, HSC-T6 cell line was under pre-disposal treatment with the blocking agents of Aldo receptor -antisterone, protein kinase C (PKC) special blocking agent-Stauro, Rho kinase blocking agent-Y27632 and MLCK special blocking agent-ML-7 respectively prior to stimulation with aldosterone. RT-PCR was used to detect the expression of Rock2, RhoAGTP and RhoGEF in Ca2+- independent pathways mediated by Rho-kinase.

Aldo could induce HSCs contraction. The concentration of intracellular free calcium in rat HSCs had no change after pre-disposal treatment with Aldo. The mRNA expressions of Rock2, RhoAGTP and RhoGEF increased significantly after treatment with Aldo (0.770+/-0.049, 0.960+/-0.096, 0.180+/-0.006, P is less than 0.01).When inhibited with antisterone, the mRNA expressions of the three elements were (0.440+/-0.166, 0.370+/-0.180 and 0.050+/-0.001, P is less than 0.01), lower than that of Aldo group, but higher in ML-7+Stauro + Aldo groups (0.940+/-0.066, 1.330+/-0.192 and 0.160+/-0.007, P is less than 0.05) as compared to the control group (0.140+/-0.023, 0.540+/-0.111 and 0.110+/-0.012). In the Y27632 + ML-7 + Stauro+Aldo group, the mRNA expression of RhoGEF (0.290+/-0.004, P is less than 0.01)was higher than that of the ML-7 + Stauro + Aldo group (0.160+/-0.007).

Aldo could induce HSCs contraction via Ca2+-independent pathways and Rho-Rock pathway involved in the process.