Determination of plasma and urinary angiotensinogen levels in rodents by newly developed ELISA.
We recently reported that urinary excretion rates of angiotensinogen provide a specific index of the intrarenal renin-angiotensin system status in angiotensin II-dependent hypertensive rats. Angiotensinogen concentrations in mouse plasma are thought to be much lower than those in rat plasma; however, detailed information is deficient due to lack of direct quantitative measurements of rodent angiotensinogen. To elucidate this issue, we have developed a quantitative method for measurement of rodent angiotensinogen using a sandwich-type ELISA. The standard curve for mouse and rat angiotensinogen exhibited a high linearity at 0.16-10 and 0.08-5 ng/ml, respectively, with correlation coefficients >0.99. While plasma angiotensinogen concentrations of male high serum IgA (HIGA) mice (IgA nephritis model animals, 1,308 +/- 47 ng/ml; n = 10) were lower than those of control BALB/c mice (1,620 +/- 384; n = 12), urinary angiotensinogen concentrations of HIGA mice (14.6 +/- 1.5 ng/ml; n = 34) were higher than those of BALB/c mice (4.6 +/- 0.1; n = 2). In a similar manner, while plasma angiotensinogen concentrations of Zucker diabetic fatty (ZDF) obese rats (type 2 diabetic model animals, 1,789 +/- 50 ng/ml; n = 5) were lower than those of control ZDF lean rats (2,296 +/- 47; n = 5), urinary angiotensinogen concentrations of ZDF obese rats (88.2 +/- 11.4 ng/ml; n = 15) were higher than those of ZDF lean rats (31.3 +/- 1.9; n = 15). These data indicate that plasma and urinary angiotensinogen concentrations are less in mice than rats. However, these data suggest that urinary angiotensinogen levels are different from plasma angiotensinogen levels in rodents. The development of rodent angiotensinogen ELISA allows quantitative comparisons in mouse and rat angiotensinogen levels in models of hypertension and cardiovascular and kidney diseases.
Kobori
Hiroyuki
H
Department of Medicine, Tulane University Health Sciences Center, New Orleans, LA 70112-2699, USA. hkobori@tulane.edu
Katsurada
Akemi
A
Miyata
Kayoko
K
Ohashi
Naro
N
Satou
Ryousuke
R
Saito
Toshie
T
Hagiwara
Yoshiaki
Y
Miyashita
Kazuya
K
Navar
L Gabriel
LG
D000808:Angiotensinogen / Q000097:blood* / Q000652:urine*; D000818:Animals; D000918:Antibody Specificity; D015153:Blotting, Western; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000139:chemically induced / Q000652:urine; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005822:Genetic Vectors; D005922:Glomerulonephritis, IGA / Q000097:blood / Q000652:urine; D007150:Immunohistochemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009765:Obesity / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011924:Rats, Zucker; D011994:Recombinant Proteins / Q000097:blood / Q000652:urine; D012083:Renin / Q000097:blood; D015203:Reproducibility of Results
D011994:Recombinant Proteins; D000808:Angiotensinogen; D012083:Renin