Neonatal losartan treatment suppresses renal expression of molecules involved in cell-cell and cell-matrix interactions
Artikel i vetenskaplig tidskrift, 2004

Lack of neonatal angiotensin II type 1 receptor (AT(1)) stimulation produces renal abnormalities characterized by papillary atrophy and impaired urinary concentrating ability, but the mechanisms involved are still unclear. DNA microarray was used to identify genes that are differentially expressed in renal medulla in response to neonatal treatment with AT(1) receptor antagonist losartan (30 mg/kg per d), which commenced within 24 h after birth. The data showed that losartan treatment for 48 h downregulated 68 genes, approximately 30% of which encode various components of cytoskeleton and cytoskeleton-associated proteins, extracellular matrix, and enzymes involved in extracellular matrix maturation or turnover. With the use of immunohistochemistry and Western immunoblot, the microarray data were confirmed and it was demonstrated that losartan suppressed renal expression of syndecan 2, alpha-smooth muscle actin, MHC class II, and leukocyte type 12-lipoxygenase by day 4. In addition, losartan inhibited medullary expression of integrin alpha6 and caused relocalization of integrins alpha6 and alpha3. Moreover, losartan inhibited cell proliferation in medullary tubules by day 9, as detected by Ki-67 immunostaining. This study provides new data supporting the contention that a lack of AT(1) receptor stimulation results in abnormal matrix assembly, disturbed cell-cell and cell-matrix interactions, and subsequent abnormal tubular maturation. Moreover, regulation of the expression of leukocyte type 12-lipoxygenase and alpha-smooth muscle actin by the renin-angiotensin system in the immature kidney adds new knowledge toward the understanding of renal vascular development.

Newborn

Oligonucleotide Array Sequence Analysis

Cell Division/drug effects

Rats

Losartan/*pharmacology

Histocompatibility Antigens Class II/genetics

Cell Communication/*drug effects

Syndecan-2

Antihypertensive Agents/*pharmacology

Kidney/drug effects/*growth & development/*pathology

Wistar

Apoptosis/drug effects

Animals

Proteoglycans/genetics

Animals

Actins/genetics

Angiotensin II Type 1 Receptor Blockers

Membrane Glycoproteins/genetics

Extracellular Matrix/drug effects

Gene Expression/drug effects

Rats

Integrin alpha3/genetics

Integrin alpha6/genetics

Arachidonate 12-Lipoxygenase/genetics

Författare

Yun Chen

Göteborgs universitet

Daina Lasaitiene

Göteborgs universitet

Britt Gabrielsson

Göteborgs universitet

Lena M S Carlsson

Göteborgs universitet

Håkan Billig

Göteborgs universitet

Björn Carlsson

Göteborgs universitet

N. Marcussen

X. F. Sun

Peter Friberg

Göteborgs universitet

Journal of the American Society of Nephrology : JASN

1046-6673 (ISSN) 1533-3450 (eISSN)

Vol. 15 5 1232-43

Ämneskategorier

Fysiologi

MEDICIN OCH HÄLSOVETENSKAP

DOI

10.1097/01.ASN.0000123690.75026.3F

PubMed

15100363