Abstract
1. 1. The relative importance of Na-K-activated ATPase in active bulk transport of Na+ in the elasmobranch kidney was examined. Fractional Na+ excretion was examined before and after the administration of ouabain, associated with over a 60 per cent reduction in enzyme activity, as well as following furosemide and ethacrynic acid. 2. 2. Marked inhibition of Na-K-ATPase with ouabain did not reduce Na+ reabsorption, in contrast to furosemide and ethacrynic acid which increased fractional excretion from 0·22 to 0·69. 3. 3. These data suggest that Na-K-ATPase does not participate in bulk transport of Na+ in the elasmobranch kidney, where the conservation of Na+ is of little importance in osmoregulation.
Original language | English (US) |
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Pages (from-to) | 417-422 |
Number of pages | 6 |
Journal | Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology |
Volume | 44 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1 1973 |
Funding
Acknowledgements-This work was supported by U.S.P.H.S. grants TIAM 5015, HE 13647-OlAl, HE 00834-22, 5501-RR05416-10, HE 5905-01 and the American Heart Association.
Keywords
- Na-K-ATPase
- Squalus acanthias
- ethacrynic acid
- furosemide
- renal reabsorption
- sodium transport
ASJC Scopus subject areas
- Physiology