Localization of adenosine receptor subtype mrna in rat outer
medullary descending vasa recta by rt-pcr.
Kreisberg, Melinda S., Erik P. Silldorff, and Thomas L. Pallone.
Department of Medicine, Division of Nephrology, Pennsylvania State
University, Hershey Medical Center, Hershey, Pennsylvania 17033 and
the University of Maryland, Baltimore, Maryland 21201
APStracts 3:0438H, 1996.
Adenosine has a multitude of functions in the kidney, including
vasoregulation of the renal vasculature. The actions of adenosine are
mediated by its binding to specific receptors. Four adenosine
receptor subtypes have been cloned and sequenced, the A 1 , A 2a , A
2b , and the A 3 . In this study, the expression of individual
adenosine receptor subtype RNAs in outer medullary descending vasa
recta (OMDVR) was investigated. Total RNA isolated from the outer
medulla and microdissected, permeabilized OMDVR were subjected to
reverse transcription-polymerase chain reaction (RT-PCR) with primers
specific for each of the adenosine receptor subtypes. Subtype
specific probes were used to verify the PCR products by Southern
hybridization. Our studies, performed in triplicate on 5 different
rats, indicate the presence of A 1 , A 2a , and A 2b adenosine
receptor subtype mRNAs. These products were not attributable to
extraneous RNA contamination from other tissue sources, nor were they
resultant from genomic DNA amplification. These data are consistent
with pharmacologic evaluations, favor A 1 , A 2a , and A 2b adenosine
receptor subtype expression in OMDVR, and support a role for
adenosine in regulation of medullary blood flow.
Received 18 June 1996; accepted in final form 30 September 1996.
APS Manuscript Number H532-6.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996