Biomaterial Database

Regulation of sodium transport by endogenous dopamine production in proximal tubular and OK cells. 1997

A D Baines, and R Drangova

Department of Clinical Biochemistry, University of Toronto, Ontario, Canada.

Inhibition of AADC for several hours increases the activity and mass of NaKATPase in proximal tubular basolateral membranes and reduces phosphate (P1) and citrate excretion, but has only a small effect on Na excretion. The reduction in citrate excretion is consistent with the observed increase in brush border Na+/H+ exchange. Thus, in Na replete rats, endogenous D inhibits Na entry into proximal tubular cells, through cotransport with Pi and exchange with H+, and inhibits exit through the Na pump. Tonic D inhibition of NaKATPase and Na+/H+ antiporter activity is not found in the SH rats' kidneys, which have defective linkage of proximal tubular D receptors to adenylate cyclase. The inhibitory action of endogenous D on Pi reabsorption is retained in SHR kidneys. This suggests that different signaling systems are responsible for the effects of D on NaPi transport and Na+/H+ exchange. In OK cells D inhibits NaPi cotransport (Ki 0.2 microM). The D effect is not blocked by cAMP, adenylate cyclase, PKA or PKC inhibitors. Thus it appears that D regulates NaPi transport by a non-cAMP, non-PKC mechanism and is a homeostatic regulator of phosphate reabsorption by SHR.

UI	MeSH Term	Description	Entries
D006973	Hypertension	Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.	Blood Pressure, High,Blood Pressures, High,High Blood Pressure,High Blood Pressures
D007687	Kidney Tubules, Proximal	The renal tubule portion that extends from the BOWMAN CAPSULE in the KIDNEY CORTEX into the KIDNEY MEDULLA. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the U-shaped LOOP OF HENLE.	Proximal Kidney Tubule,Proximal Renal Tubule,Kidney Tubule, Proximal,Proximal Kidney Tubules,Proximal Renal Tubules,Renal Tubule, Proximal,Renal Tubules, Proximal,Tubule, Proximal Kidney,Tubule, Proximal Renal,Tubules, Proximal Kidney,Tubules, Proximal Renal
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D015222	Sodium Channels	Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.	Ion Channels, Sodium,Ion Channel, Sodium,Sodium Channel,Sodium Ion Channels,Channel, Sodium,Channel, Sodium Ion,Channels, Sodium,Channels, Sodium Ion,Sodium Ion Channel
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus