Biomaterial Database

Arginine vasopressin increases renal sodium excretion in the anesthetized rat through V1 receptors. 1997

C T Musabayane, and M L Forsling, and R J Balment

Department of Physiology, University of Zimbabwe, Harare, Zimbabwe.

We have previously suggested that the increase in renal Na+ excretion in response to physiological doses of arginine vasopressin (AVP) is not directly linked to the V2-mediated antidiuretic effect. In the present study we investigated the possible involvement of AVP V1 receptors in this natriuresis using a specific AVP V1 antagonist [1-(beta-mercapto-beta, beta-cyclopentamethylenepropionic acid), 2-O-methyltyrosine arginine vasopressin, d(CH2)5[Tyr(Me)2]AVP, infused at a rate of 15 ng.min-1. Male anesthetized Sprague-Dawley rats were placed on a continuous jugular infusion of 0.077 M NaCl at 150 microL.min-1. After a 3-h equilibration period, samples were collected at 20-min intervals for 4 h for the determination of urine flow, and Na+ and K+ excretion rates. In those animals in which the effects of AVP were studied, a 1-h control period was allowed following which AVP was infused at 0.02-0.08 pmol.min-1 for 1 h 20 min in separate groups of animals and then returned to the infusate alone for the last part of the experiment. In other groups the AVP V1 antagonist d(CH2)5[Tyr(Me)2]AVP (15 ng.min-1) alone or in combination with AVP (at various dose rates) was also administered for 1 h 20 min. All dose rates of AVP produced an antidiuresis which was associated significantly to increased Na+ excretion rate. However, AVP administration at the median dose rate (0.04 pmol.min-1) significantly (p < 0.01) decreased the amount of urine voided by comparison with control animals (6.34 +/- 1.05 ml vs. 11.892 +/- 0.03 mL, n = 7) although the urinary Na+ was elevated (967 +/- 18 mumol, vs. 742 +/- 81 mumol, n = 7). This AVP-induced increase in urinary Na+ loss was abolished in animals receiving combined AVP (0.04 pmol.min-1) and AVP V1 antagonist (674 +/- 47 mumol, n = 7) although the antidiuretic effect persisted. Urine flow and Na+ excretion rates remained unchanged in groups of animals administered AVP V1 antagonist alone. In all groups, the K+ excretion rates did not significantly differ. It is concluded that the V1 receptor mediates the natriuretic effect of AVP.

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
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008297	Male		Males
D009318	Natriuresis	Sodium excretion by URINATION.	Natriureses
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D012076	Renal Agents	Drugs used for their effects on the kidneys' regulation of body fluid composition and volume. The most commonly used are the diuretics. Also included are drugs used for their antidiuretic and uricosuric actions, for their effects on the kidneys' clearance of other drugs, and for diagnosis of renal function.	Agents, Renal
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005919	Glomerular Filtration Rate	The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance.	Filtration Rate, Glomerular,Filtration Rates, Glomerular,Glomerular Filtration Rates,Rate, Glomerular Filtration,Rates, Glomerular Filtration
D000758	Anesthesia	A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
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