Temporal and spatial expression pattern of the angiotensinogen gene
in mice and rats.
Niimura, Fumio, Soichiro Okubo, Agnes Fogo, and Iekuni Ichikawa.
Departments of Pediatrics and Pathology, Vanderbilt University
School of Medicine, Nashville, Tennessee, U.S.A. 37232
APStracts 3:0235R, 1996.
In situ hybridization for mouse angiotensinogen (Ao) mRNA was
performed using a StuI-PstI 0.43kb fragment of exon 2 as a template
to synthesize RNA probes. The mouse Ao mRNA expression patterns were
different from those reported for rats. Ao mRNA was expressed in the
fetal liver as early as 12.5 days post coitus (p.c.), and the liver
remained the predominant organ of its expression in utero. Within the
developing kidney, Ao mRNA was demonstrated at 17.5 days p.c. in the
proximal straight tubules undergoing loop formation in the medulla.
In the matured mouse kidney, the expression site is within the outer
stripe of outer medulla, hence, identified as the pars recta, not
proximal convoluted tubules. Additional studies revealed that, in
rats also, Ao mRNA was localized in the pars recta. This was in
contrast to previously published results that showed that Ao mRNA was
localized primarily in the proximal convoluted tubules in rats. Thus,
the pars recta appears to be an important intrarenal source of Ao for
both rats and mice throughout pre- and postnatal periods while the
liver can be the major extrarenal source in utero in mice, but not in
rats.
Received 12 September 1995; accepted in final form 6 June 1996.
APS Manuscript Number R563-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96