Biomaterial Database

Renal response to amino acid infusion in rats: effect of dopamine receptor antagonists and benserazide. 1994

B Mühlbauer, and E Hartenburg, and H Osswald

Pharmakologisches Institut, Universität Tübingen, Germany.

Previously, we have found that feeding is a dominant factor controlling urinary dopamine excretion (UDA) in conscious rats (Mühlbauer and Osswald 1992). Since the renal response to feeding is also characterized by an increase in glomerular filtration rate (GFR), we wanted to investigate in a first step whether the feeding-induced elevations of GFR and UDA could be causally related phenomena. Therefore, we studied the influence of dopamine synthesis and dopamine receptor blockade on the renal response to amino acid infusion (AA) in thiopental anesthetized rats. AA infusion (n = 7) increased GFR by 33 +/- 7% (P < 0.001) and UDA by 87 +/- 19% (P < 0.001). In the presence of benserazide (BZD, n = 5), an inhibitor of dopamine synthesis, infused i.v. at a dose of 30 micrograms/min/kg, UDA was suppressed to values below detection limit and the AA-induced GFR increase was abolished. Continuous intravenous infusion of the DA1 receptor antagonist SCH 23390 (SCH, n = 7) in a dose of 4.0 micrograms/kg/min did not prevent the AA-induced increase in GFR (33 +/- 3%, P < 0.001) and UDA (97 +/- 12%, P < 0.001). In contrast, S-sulpiride (SUL), a specific DA2 receptor antagonist, infused continuously i.v. in a dose of 5 micrograms/kg/min, completely abolished the AA-induced GFR increase, while UDA was increased 1.6-fold (P < 0.01). Like BZD, both dopamine receptor antagonists did not affect renal sodium excretion substantially. Our results suggest, that endogenous dopamine could act as a mediator in the renal response to amino acid infusion in the rat, most likely by activation of DA2 receptors.

UI	MeSH Term	Description	Entries
D007262	Infusions, Intravenous	The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.	Drip Infusions,Intravenous Drip,Intravenous Infusions,Drip Infusion,Drip, Intravenous,Infusion, Drip,Infusion, Intravenous,Infusions, Drip,Intravenous Infusion
D007444	Inulin	A starch found in the tubers and roots of many plants. Since it is hydrolyzable to FRUCTOSE, it is classified as a fructosan. It has been used in physiologic investigation for determination of the rate of glomerular function.
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D007677	Kidney Function Tests	Laboratory tests used to evaluate how well the kidneys are working through examination of blood and urine.	Function Test, Kidney,Function Tests, Kidney,Kidney Function Test,Test, Kidney Function,Tests, Kidney Function
D008297	Male		Males
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
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
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
D001545	Benserazide	An inhibitor of DOPA DECARBOXYLASE that does not enter the central nervous system. It is often given with LEVODOPA in the treatment of parkinsonism to prevent the conversion of levodopa to dopamine in the periphery, thereby increasing the amount that reaches the central nervous system and reducing the required dose. It has no antiparkinson actions when given alone.	Serazide,Seryltrihydroxybenzylhydrazine,DL-Serine 2-((2,3,4-trihydroxyphenyl)methyl)hydrazide,Ro 4-4602,Seryltrihydroxy Benzylhydrazine,Benzylhydrazine, Seryltrihydroxy,Ro 4 4602,Ro 44602
D001552	Benzazepines	Compounds with BENZENE fused to AZEPINES.