Na-K-ATPase in nephron segments of rats developing spontaneous hypertension.
Na-K-ATPase activity was determined in seven specific nephron segments of 5- and 12-wk-old spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) controls. The enzyme activity in proximal convoluted tubule (PCT) and proximal straight tubule (PST) was significantly higher in 5-wk-old SHR than in WKY. However, Na-K-ATPase activity in medullary thick ascending limb (MTAL), cortical thick ascending limb (CTAL), and distal convoluted tubule (DCT) was significantly lower in 5-wk-old SHR than in WKY. There were no significant differences in the enzyme activity in PCT, PST, MTAL, CTAL, and DCT in 12-wk-old SHR and WKY. Furthermore, there were no significant differences in Na-K-ATPase activity in collecting duct segments of 5- or 12-wk-old SHR and age-matched WKY. The possible role of the abnormal pattern of Na-K-ATPase activity in PCT, PST, MTAL, CTAL, and DCT in 5-wk-old SHR in generation of hypertension in this strain remains to be determined.
D000367:Age Factors; D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D004032:Diet; D006973:Hypertension / Q000201:enzymology* / Q000235:genetics; D008297:Male; D009399:Nephrons / Q000201:enzymology*; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012964:Sodium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D014018:Tissue Distribution
D012964:Sodium; D017301:Ca(2+) Mg(2+)-ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium