Long-term EGF treatment partially prevents reduction of renal blood flow in response to neonatally induced partial unilateral ureteral obstruction.
OBJECTIVE
To investigate the effects of long-term epidermal growth factor (EGF) treatment on kidney growth, renal blood flow (RBF), AQP2 expression and urine output in newborn rats with partial unilateral ureteral obstruction (PUUO).


METHODS
PUUO (n = 29) and sham-operated control (CON) (n = 26) was created in 2-day-old rats. Fifteen PUUO and 14 CON rats were treated with EGF beginning from the second day after operation to 8 weeks of age. Total kidney volume (TKV) and RBF were measured by MRI at weeks 4 and 8, respectively. Urine volume and osmolality, plasma osmolality, and free water clearance were measured. Renal AQP2 expression was determined using semiquantitative immuno-blotting.


RESULTS
PUUO induced a severe hydronephrosis and RBF reduction in the obstructed kidney which was attenuated in EGF-treated rats. Body weight, urine output and free water clearance increased, osmolality and the osmolar clearance decreased significantly in EGF-treated rats, despite unchanged AQP2 levels.


CONCLUSIONS
Long-term EGF treatment attenuated the obstruction- induced RBF reduction. Body weight, urine output increased, and urine osmolality decreased in both control and PUUO rats treated with EGF. Solute-free water clearance increased in PUUO rats which seem to be independent of AQP2 expression.
Wen
Jian Guo
JG
Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark.
Wang
Gui Xian
GX
Chen
Yue
Y
Ringgaard
Steffen
S
Vinter-Jensen
Lars
L
Jørgensen
Troels Munch
TM
Li
Zhenzhen
Z
Stødkilde-Jørgensen
Hans
H
Nielsen
Søren
S
Djurhuus
Jens Christian
JC
Frøkiaer
Jørgen
J
D000818:Animals; D000831:Animals, Newborn; D004815:Epidermal Growth Factor / Q000008:administration & dosage*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012079:Renal Circulation / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors; D014517:Ureteral Obstruction / Q000188:drug therapy* / Q000503:physiopathology / Q000652:urine
D004815:Epidermal Growth Factor