Increased pressure induces sustained protein kinase C-independent herbimycin A-sensitive activation of extracellular signal-related kinase 1/2 in the rabbit aorta in organ culture.
The 42- and 44-kD mitogen-activated protein kinases, also referred to as extracellular signal-related kinase (ERK) 2 and 1, respectively, may be transiently activated by stretching vascular smooth muscle cells (VSMCs). Using an organ culture model of rabbit aorta, we studied short- and long-term ERK1/2 activation by intraluminal pressure (150 mm Hg). Activation of ERK1/2 was biphasic: it reached a maximum (217.5 +/- 8.4% of control) 5 minutes after pressurizing and decreased to 120.7 +/- 5.1% of control after 2 hours. Furthermore, after 24 hours of pressurizing, ERK1/2 activity was as high (241.8 +/- 14.7% of control) as in the acute phase. Long-term pressure-induced ERK1/2 activation correlated with stimulation of tyrosine phosphorylation of proteins in the 125- to 140-kD range. Neither protein kinase C inhibitors (1 mumol/L staurosporine or 50 mumol/L bisindolylmaleimide-I) nor tyrosine kinase inhibitors (50 mumol/L tyrphostin A48 or 50 mumol/L genistein) affected pressure-induced ERK1/2 activation. However, the Src-family tyrosine kinase inhibitor herbimycin A (500 nmol/L) did reduce both 5-minute (by 92 +/- 8%) and 24-hour (by 63 +/- 7%) pressure-induced ERK1/2 activation. Thus, our results demonstrate a sustained activation of ERK1/2 and tyrosine kinases by intraluminal pressure in the arterial wall. Pressure-induced ERK1/2 activation is PKC independent and Src-family tyrosine kinase dependent and possibly includes activation of extracellular matrix-associated tyrosine kinases.
Birukov
K G
KG
INSERM U-141, Hôpital Lariboisière, Paris, France.
Lehoux
S
S
Birukova
A A
AA
Merval
R
R
Tkachuk
V A
VA
Tedgui
A
A
D000818:Animals; D001011:Aorta / Q000201:enzymology*; D016227:Benzoquinones; D001794:Blood Pressure; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D047029:Lactams, Macrocyclic; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D009924:Organ Culture Techniques; D010766:Phosphorylation; D011493:Protein Kinase C / Q000502:physiology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D011809:Quinones / Q000494:pharmacology*; D011817:Rabbits; D017828:Rifabutin / Q000031:analogs & derivatives; D014443:Tyrosine / Q000378:metabolism
D016227:Benzoquinones; D004791:Enzyme Inhibitors; D047029:Lactams, Macrocyclic; D011809:Quinones; D017828:Rifabutin; D014443:Tyrosine; C020754:herbimycin; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases