Background　Little　information　is　available　regarding　the　effect　of　angiotensin　U　(Ang　R)　on　the　bumetanide-sensitive　sodium-potassium-2　chloride　cotransporter　(NKCC2)　I　the　thiazide-sensitive　sodium-chloride　cotransporter　(NCC),　and　the　Cl-　channel.　(CLC)-K-2,　at　both　mRNA　and　protein　expression　level　in　Ang　II-induced　hypertensive　rats.　This　study　was　conducted　to　investigate　the　influence　of　Ang　R　with　chronic　subpressor　infusion　on　nephron-specific　gene　expression　of　NKCC2,　NCC　and　CLC-K-2.　Methods　Sprague　Dawleys　rats　were　treated　subcutaneously　with　either　Ang　11　(　100　ng　(.)　kg(-1)　(.)　min(-1))　or　vehicle　for　14　days.　Expression　of　NKCC2,　NCC　and　CLC-K-2　mRNA　in　kidneys　was　determined　by　real　time　polymerase　chain　reaction　(PCR).　Western　blotting　analysis　was　used　to　measure　NKCC2　and　NCC　protein　expression.　Results　Ang　11　significantly　increased　blood　pressure　and　up-regulated　NKCC2,　mRNA　and　protein　expression　in　the　kidney.　Expression　of　CLC-K-2,　mRNA　in　the　kidney　increased　1.6　fold　(P＜0.05　There　were　no　changes　in　NCC　mRNA　or　protein　expression　in　AngII-treated　rats　versus　control.　Conclusions　Chronic　subpressor　Ang　R　infusion　can　significantly　alter　NKCC2,　and　CLC-K-2　mRNA　expression　in　the　kidney,　and　protein　abundance　of　NKCC2,　in　kidney　is　positively　regulated　by　Ang　U.　These.　effects　may　contribute　to　enhanced　renal　Na+　and　Cl-　reabsorption　in　response　to　Ang　II.