Kidney Outer Medulla Research Articles

The effects of long-chain alcohols on membrane lipids and the (Na + + K +)-ATPase

The (Na + + K +)-ATPase obtained from sheep kidney outer medulla is irreversibly denatured by long-chain aliphatic alcohols. The denaturation proceeds by causing a change in the structure of the membrane lipids rather than by binding directly to the protein. The alcohols decrease the ability of the membrane lipid bilayer to orient the spin label 3-(4′,4′-dimethyloxazolidinyl)-5α-androstan-17β-ol. For the low molecular weight alcohols the ability of the membrane to orient the label is completely lost while for alcohols with more than five carbons only partial loss of the orienting ability of the membrane occurs. The alcohol concentrations necessary to denature the enzyme correspond to the concentrations that produce the maximal change in the ability of the membrane to orient the label, and correlate well with the hydrophobicity of the alcohols as measured by their water-octanol partition coefficients.

Influence of ethacrynic acid and ouabain on the oxygen consumption and potassium and sodium content of the kidney external medulla of the dog

1. 1. The effect of ethacrynic acid and ouabain on the oxygen consumption of dog kidney outer medulla was studied and compared with their influence on K + and Na + content of the tissue. 2. 2. Ethacrynic acid inhibited oxygen consumption; maximum inhibition was obtained with 1 mM of the diuretic; the lowering of K + content was not parallel to the effect on respiration, and the increase of Na + content was greater than the influence on K + uptake. 3. 3. When NaCl was replaced by choline chloride or lactose in the incubation medium, no effect of ethacryic acid on Q O2 or K + content was obtained. 4. 4. Ouabain diminished oxygen consumption and produced a parallel reduction in K + content; there was a proportional increase in Na + content at all concentrations employed. The maximal effect was obtained with 1 μM of the drug. 5. 5. Varying ethacrynic acid concentration in the presence of 1 μM ouabain, an inhibition of Q O2 was obtained, but to a lesser degree than that which took place when the diuretic was acting alone; K + content was not affected and Na + content was augmented. 6. 6. The above results are discussed in relation with the hypothesis of two pumps involved in Na + extrusion (as proposed for kidney cortex): one pump exchanges Na + for K +, depends on ATP hydrolysis by (Na +−K +)-ATPase and is sensitive to ouabain and ethacrynic acid; the other expels Na + not coupled to K + influx, is insensitive to ouabain and sensitive to ethacrynic acid.

Renal response to solute loading in infant rats: relation to anatomical development.

ARTICLESRenal response to solute loading in infant rats: relation to anatomical developmentME TrimbleME TrimblePublished Online:01 Oct 1970https://doi.org/10.1152/ajplegacy.1970.219.4.1089MoreSectionsPDF (3 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByGlucocorticoid impairs growth of kidney outer medulla and accelerates loop of Henle differentiation and urinary concentrating capacity in rat kidney developmentJane Stubbe, Kirsten Madsen, Finn Thomsen Nielsen, Ole Skøtt, and Boye L. Jensen1 October 2006 | American Journal of Physiology-Renal Physiology, Vol. 291, No. 4Expression of aldose reductase in developing rat kidneyJu-Young Jung, Young-Hee Kim, Jung-Ho Cha, Ki-Hwan Han, Moo-Kang Kim, Kirsten M. Madsen, and Jin Kim1 September 2002 | American Journal of Physiology-Renal Physiology, Vol. 283, No. 3Expression of urea transporters in the developing rat kidneyYoung-Hee Kim, Dong-Un Kim, Ki-Hwan Han, Ju-Young Jung, Jeff M. Sands, Mark A. Knepper, Kirsten M. Madsen, and Jin Kim1 March 2002 | American Journal of Physiology-Renal Physiology, Vol. 282, No. 3Developmental expression of aquaporin 1 in the rat renal vasculatureJin Kim, Wan-Young Kim, Ki-Hwan Han, Mark A. Knepper, Søren Nielsen, and Kirsten M. Madsen1 April 1999 | American Journal of Physiology-Renal Physiology, Vol. 276, No. 4 More from this issue > Volume 219Issue 4October 1970Pages 1089-1097 Copyright & PermissionsCopyright © 1970 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1970.219.4.1089PubMed5459474History Published online 1 October 1970 Published in print 1 October 1970 Metrics