The role of tyrosine kinase in the contraction of rat mesenteric artery.

The phosphorylation of proteins on tyrosine residues by tyrosine kinases has been suggested to contribute to signalling processes that lead to smooth muscle contraction. The aim of the current study was to further determine the role of tyrosine kinase in the contraction of rat vascular smooth muscle. The specific objectives included (i) studying the effect of tyrosine kinase inhibitors on vascular contraction induced by noradrenaline (NA), potassium chloride (KCl) and neuropeptide V (NPY); (ii) studying the effect of sodium orthovanadate on contraction; (iii) studying the role of endothelium dependence in contraction; as well as (iv) studying the role of L-type Ca$\sp{2+}$ channels in the tyrosine kinase-related response. The effects of NPY, nifedipine, sodium orthovanadate and various tyrosine kinase inhibitors were tested in intact ring segments of rat mesenteric and tail arteries. The present studies illustrate that tyrosine kinase plays an important role in signal transduction stimulated by agonists in vascular smooth muscle. (Abstract shortened by UMI.