H-1152

Kinase experiment:

Inhibitors (including H-1152) are added at the indicated concentrations to 50 µL of the assay mixture 50 mM Tris-HCl (pH 7.5), 5 mM MgCl2, 1 mM EDTA, 1 mM EGTA, 1 mM dithiothreitol, 40 µM S6-peptide, various concentrations of [γ-32P]ATP and purified Rho-kinase. The reactions are started by the addition of [γ-32P]ATP and carried out at 30°C for 5 min. The Michaelis-Menten equation is used to calculate the Michaelis constant (Km) and maximal velocity (Vmax) of Rho-kinase. Data are further analyzed with secondary plot to calculate the inhibitory constant (Ki)[2].

Cell experiment:

Briefly, cells are routinely plated on poly-d-lysine/laminin coated 96 well plates or in 16 well glass culture slides. Control medium contained Dulbecco's modified Eagles medium/Hams F12(1:1) (DMEM/F12), 2 mM l-glutamine, N2 mix (1:100 dilution), 0.63 mL of 45% glucose for each 100 mL of DMEM/F12, neurotrophin 3 (NT3; final concentration, 8 ng/mL), BDNF (final concentration 8 ng/mL), and 10% fetal bovine serum heat inactivated before use. LIF cultures contain control medium+LIF (50 ng/mL). BMP4 cultures contain control medium+bone morphogenetic protein 4 (BMP4; 25 ng/mL). Total volume of culture is 110 μL. ROCK inhibitor H-1152 is diluted in water and added in an additional 10 μL to cultures 24 h after plating. Water is added to controls. Eighteen hours after the addition of inhibitor, cultures are fixed in 4% paraformaldehyde (1 h at room temperature for peroxidase-linked labeling and 20 min at room temperature for fluorescence labeling). For ArrayScan/Cellomics automated analysis: Cells are plated in a total volume of 50 μL on 384 well plastic plates previously coated with poly-d-lysine/laminin, and cultured in the same medium[3].

References:

[1]. Tamura M, et al. Development of specific Rho-kinase inhibitors and their clinical application. Biochim Biophys Acta. 2005 Dec 30;1754(1-2):245-52. Epub 2005 Sep 12.
[2]. Ikenoya M, et al. Inhibition of rho-kinase-induced myristoylated alanine-rich C kinase substrate (MARCKS) phosphorylation in human neuronal cells by H-1152, a novel and specific Rho-kinase inhibitor. J Neurochem. 2002 Apr;81(1):9-16.
[3]. Lie M, et al. Accelerated neurite growth from spiral ganglion neurons exposed to the Rho kinase inhibitor H-1152. Neuroscience. 2010 Aug 25;169(2):855-62.