Collecting duct-specific knockout of endothelin-1 causes hypertension and sodium retention.
In vitro studies suggest that collecting duct-derived (CD-derived) endothelin-1 (ET-1) can regulate renal Na reabsorption; however, the physiologic role of CD-derived ET-1 is unknown. Consequently, the physiologic effect of selective disruption of the ET-1 gene in the CD of mice was determined. Mice heterozygous for aquaporin2 promoter Cre recombinase and homozygous for loxP-flanked exon 2 of the ET-1 gene (called CD-specific KO of ET-1 [CD ET-1 KO] mice) were generated. These animals had no CD ET-1 mRNA and had reduced urinary ET-1 excretion. CD ET-1 KO mice on a normal Na diet were hypertensive, while body weight, Na excretion, urinary aldosterone excretion, and plasma renin activity were unchanged. CD ET-1 KO mice on a high-Na diet had worsened hypertension, reduced urinary Na excretion, and excessive weight gain, but showed no differences between aldosterone excretion and plasma renin activity. Amiloride or furosemide reduced BP in CD ET-1 KO mice on a normal or high-Na diet and prevented excessive Na retention in salt-loaded CD ET-1 KO mice. These studies indicate that CD-derived ET-1 is an important physiologic regulator of renal Na excretion and systemic BP.
Ahn
Dowhan
D
Division of Nephrology, University of Utah Health Sciences Center, 1900 East 30 North, Salt Lake City, UT 84132, USA.
Ge
Yuqiang
Y
Stricklett
Peter K
PK
Gill
Pritmohinder
P
Taylor
Deborah
D
Hughes
Alisa K
AK
Yanagisawa
Masashi
M
Miller
Lance
L
Nelson
Raoul D
RD
Kohan
Donald E
DE
D000450:Aldosterone / Q000652:urine; D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004232:Diuretics / Q000494:pharmacology; D019332:Endothelin-1 / Q000235:genetics* / Q000502:physiology*; D005665:Furosemide / Q000494:pharmacology; D006579:Heterozygote; D006720:Homozygote; D006955:Hypernatremia / Q000209:etiology*; D006973:Hypertension / Q000209:etiology*; D017403:In Situ Hybridization; D007685:Kidney Tubules, Collecting / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D012333:RNA, Messenger / Q000235:genetics; D017673:Sodium Chloride, Dietary / Q000494:pharmacology / Q000652:urine; D015430:Weight Gain / Q000187:drug effects
D004232:Diuretics; D019332:Endothelin-1; D012333:RNA, Messenger; D017673:Sodium Chloride, Dietary; D000450:Aldosterone; D000584:Amiloride; D005665:Furosemide