Influence of sodium balance on urinary excretion of immunoreactive kinins in rats

Journal Article · Thu Mar 31 23:00:00 EST 1988 · Am. J. Physiol.; (United States)

OSTI ID:6970745

Barabe, J; Huberdeau, D; Bernoussi, A

Antibodies against bradykinin (BK) and its metabolites, namely des-Arg9-BK and des-Phe8,Arg9-BK were raised in rabbits, and specific radioimmunoassays (RIA) for these peptides were developed. Specificity studies showed that each RIA was specific for its antigen, since the cross-reactivities of various kinin-related peptides were less than 1.5%. The lowest concentration of peptide that could be measured in these assays was approximately 60 pg/ml. The antibodies were used to measure concentrations of BK and its metabolites in urine and kidneys of rats maintained on different sodium balance for 5 wk. The results showed that normal rats excrete low quantities of BK (63.78 +/- 2.98 ng/day, 88 determinations). The urinary excretion of des-Arg9-BK averaged 77.69 +/- 5.53 ng/day, whereas the amount of des-Phe8,Arg9-BK is equal to 7.13 +/- 0.42 ng/day. Sodium loading brings about a small decrease in the concentration of BK (45.57 +/- 2.36 ng/day, 76 determinations), whereas sodium depletion significantly increased the excretion of BK (94.23 +/- 5.50, 102 determinations, P less than 0.01) accompanied by no modification of the excretion of metabolites. Regression analysis of the results showed a positive correlation between urinary volume and BK in control and sodium-loaded animals and urinary BK and sodium in the sodium-loaded group. In kidney homogenates, sodium depletion increased not only the concentration of BK (10-fold) but also that of des-Arg9-BK and des-Phe8,Arg9-BK by a factor of four and two, respectively, when compared with normal and sodium-loaded animals. These results support the hypothesis that the renal kallikrein-kinin system may be regulated by corticosteroids.

• Research Organization: Universite de Sherbrooke, Quebec (Canada)
• OSTI ID: 6970745
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 254; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METALS
ANIMALS
ANTIBODIES
ANTIGEN-ANTIBODY REACTIONS
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BODY FLUIDS
BRADYKININ
CLEARANCE
ELEMENTS
EXCRETION
IMMUNOASSAY
IMMUNOLOGY
ISOTOPE APPLICATIONS
KININS
MAMMALS
MATERIALS
MATHEMATICS
METABOLITES
METALS
ORGANIC COMPOUNDS
PEPTIDES
POLYPEPTIDES
PROTEINS
RABBITS
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RATS
REGRESSION ANALYSIS
RODENTS
SODIUM
SPECIFICITY
STATISTICS
TRACER TECHNIQUES
URINE
VERTEBRATES
WASTES