Regulation and pharmacological blockade of sodium-potassium ATPase: a novel pathway to neuropathy.

Inflammation causes upregulation of NaV1.7 sodium channels in the associated dorsal root ganglia (DRG). The resultant increase in sodium influx must be countered to maintain osmotic homeostasis.

Stretch-induced TRPC4 downregulation is accompanied by reduced capacitative Ca2+ entry in WKY but not SHR mesenteric smooth muscle cells.

Our previous work showed that a 6-hour cyclic stretch significantly decreases TRPC4 protein expression and capacitative Ca(2+) entry in vascular smooth muscle cells from Sprague-Dawley rats. To parallel these studies, mesenteric smooth muscle cells from spontaneously hypertensive rats (SHR) and their normotensive controls, Wistar Kyoto (WKY) rats, were subjected to stretch. TRPC4 protein expression was evaluated by Western blot and Ca(2+) mobilization was measured using fura-2.

Involvement of rho kinase in the ouabain-induced contractions of the rat renal arteries.

Agonist and depolarization-induced vascular smooth muscle contractions include the activation of rho/rho kinase pathway. However, there are no reports addressing the question whether this pathway is involved in ouabain-induced vascular smooth muscle contractions. Therefore, in this study, the possible participation of the rho/rho kinase pathway in ouabain-induced contractions was evaluated in rat renal arteries.

Effects of HA-1077 and Y-27632, two rho-kinase inhibitors, in the human umbilical artery.

A role for the small G protein rho and rho-kinase has been shown in smooth muscle contraction regarding Ca++ sensitivity. However, there are no data in the literature assessing how this system operates in human umbilical arteries (HUA). Therefore, we evaluated the effects of HA-1077 and Y-27632, two rho-kinase inhibitors, on agonist-(5-hydroxytryptamine [5-HT]) and depolarization-induced (KCl) contractions of HUA.

Short-term stretch translocates the alpha-1-subunit of the Na pump to plasma membrane.

Short-term (2 30 min) cyclic stretch activates the Na pump in cultured aortic smooth muscle cells (ASMCs). This effect of stretch involves the phosphotidylinositol 3-kinase (PI 3-kinase) participation. Presently, we investigated whether this stimulation is the result of translocation of Na(+),K(+)-ATPase from endosomes to the plasma membrane.