AJP - Endocrinology and Metabolism, Vol 260, Issue 5 E675-E679, Copyright © 1991 by American Physiological Society

ARTICLES

Effects of high salt intake on dopamine production in rat kidney

M. Hayashi, Y. Yamaji, W. Kitajima and T. Saruta
Department of Internal Medicine, Social Insurance Saitama Chuo Hospital, Tokyo, Japan.

To examine the origin of increased urinary dopamine excretion (UDAV) during high salt intake, we measured UDAV from the innervated (INN) or the chronically denervated (DEN) kidney in rats fed either a high-salt (HS) or low-salt (LS) diet. UDAV of DEN [3.50 +/- 0.46 ng. min-1.inulin clearance (CIN)-1] and INN (4.00 +/- 0.59 ng. min-1.CIN-1) kidneys in the HS group showed a significant increase compared with that of the respective kidney in the LS group (DEN 1.42 +/- 0.12, INN 1.44 +/- 0.09 ng.min-1.CIN-1), whereas the effect of denervation on UDAV was not significantly different between two groups. We determined aromatic L-amino acid decarboxylase (L-AADC) activity and dopamine degradation rate of microdissected proximal convoluted tubules to study the changes in dopamine metabolism. L-AADC activity in the HS group showed a significant increase compared with that in the LS group, although there was no significant change in dopamine degradation rate. We conclude that the increase in UDAV during high salt intake was mainly caused by the enhancement of extraneural dopamine production by the kidney in rats. Dopamine-producing enzyme, but not its degradation in the tubular cells, plays a role in the regulation of extraneural dopamine production.

This article has been cited by other articles:

				A. Maurel, O. Spreux-Varoquaux, F. Amenta, S. K. Tayebati, D. Tomassoni, M.-H. Seguelas, A. Parini, and N. Pizzinat Vesicular monoamine transporter 1 mediates dopamine secretion in rat proximal tubular cells Am J Physiol Renal Physiol, May 1, 2007; 292(5): F1592 - F1598. [Abstract] [Full Text] [PDF]

				C. Zeng, H. Sanada, H. Watanabe, G. M. Eisner, R. A. Felder, and P. A. Jose Functional genomics of the dopaminergic system in hypertension Physiol Genomics, November 17, 2004; 19(3): 233 - 246. [Abstract] [Full Text] [PDF]

				P. Soares-Da-Silva and M. P. Serrao Molecular modulation of inward and outward apical transporters of L-dopa in LLC-PK1 cells Am J Physiol Renal Physiol, October 1, 2000; 279(4): F736 - F746. [Abstract] [Full Text] [PDF]

				M. A. Vieira-Coelho, T. Hussain, V. Kansra, M. P. Serrao, J. T. Guimaraes, M. Pestana, P. Soares-da-Silva, and M. F. Lokhandwala Aging, High Salt Intake, and Renal Dopaminergic Activity in Fischer 344 Rats Hypertension, October 1, 1999; 34(4): 666 - 672. [Abstract] [Full Text] [PDF]

				P. Soares-Da-Silva, M. P. Serrao, and M. A. Vieira-Coelho Apical and basolateral uptake and intracellular fate of dopamine precursor L-dopa in LLC-PK1 cells Am J Physiol Renal Physiol, February 1, 1998; 274(2): F243 - F251. [Abstract] [Full Text] [PDF]

				M. C. Hu, L. Fan, L. A. Crowder, Z. Karim-Jimenez, H. Murer, and O. W. Moe Dopamine Acutely Stimulates Na+/H+ Exchanger (NHE3) Endocytosis via Clathrin-coated Vesicles. DEPENDENCE ON PROTEIN KINASE A-MEDIATED NHE3 PHOSPHORYLATION J. Biol. Chem., July 13, 2001; 276(29): 26906 - 26915. [Abstract] [Full Text] [PDF]