Renal uptake and excretion of epidermal growth factor from plasma in the rat

TY - JOUR

T1 - Renal uptake and excretion of epidermal growth factor from plasma in the rat

AU - Jørgensen, Per E.

AU - Rasmussen, Torben N.

AU - Olsen, Peter Skov

AU - Raaberg, Lasse

AU - Poulsen, Steen Seier

AU - Nexø, Ebba

PY - 1990/5/21

Y1 - 1990/5/21

N2 - The rat excretes around 2 nmol epidermal growth factor (EGF) in the urine per 24 h. The urinary EGF might be derived from plasma and/or might be synthesized in the kidneys. We have used the rat to study the renal uptake and excretion of homologous EGF from plasma. I.v. injected 125I-EGF was removed from the circulation within a few minutes. 5 min after the injection, the kidneys contained 12% of the 125I-EGF. The kidneys seemed to degrade most of the 125I-EGF which they accumulated from blood, as only 4% of the injected label was excreted as intact 125I-EGF in the urine. The amount of endogenous EGF in plasma was under the detection limit of our enzyme-linked immunosorbent assay (0.03 nmol/l) and it remained so after bilateral nephrectomy. Even if plasma EGF was 0.03 nmol/l excretion of EGF from plasma could account for less than 5% of the urinary EGF. This study shows that the kidneys are able to accumulate EGF from plasma and excrete a part of it as intact EGF in the urine. However, excretion of immunoreactive EGF from plasma can only account for a minor part of the urinary EGF.

AB - The rat excretes around 2 nmol epidermal growth factor (EGF) in the urine per 24 h. The urinary EGF might be derived from plasma and/or might be synthesized in the kidneys. We have used the rat to study the renal uptake and excretion of homologous EGF from plasma. I.v. injected 125I-EGF was removed from the circulation within a few minutes. 5 min after the injection, the kidneys contained 12% of the 125I-EGF. The kidneys seemed to degrade most of the 125I-EGF which they accumulated from blood, as only 4% of the injected label was excreted as intact 125I-EGF in the urine. The amount of endogenous EGF in plasma was under the detection limit of our enzyme-linked immunosorbent assay (0.03 nmol/l) and it remained so after bilateral nephrectomy. Even if plasma EGF was 0.03 nmol/l excretion of EGF from plasma could account for less than 5% of the urinary EGF. This study shows that the kidneys are able to accumulate EGF from plasma and excrete a part of it as intact EGF in the urine. However, excretion of immunoreactive EGF from plasma can only account for a minor part of the urinary EGF.

KW - Blood

KW - Epidermal growth factor

KW - Kidney

KW - Metabolism

KW - Rat

KW - Urine

UR - http://www.scopus.com/inward/record.url?scp=0025231281&partnerID=8YFLogxK

U2 - 10.1016/0167-0115(90)90025-R

DO - 10.1016/0167-0115(90)90025-R

M3 - Journal article

C2 - 2377743

AN - SCOPUS:0025231281

SN - 0167-0115

VL - 28

SP - 273

EP - 280

JO - Regulatory Peptides

JF - Regulatory Peptides

IS - 3

ER -