Molecular evidence for a vascular smooth muscle h+,k+-atpase.
Marrelli, Sean P., Xun Zhao, and Julius C. Allen.
Departments of Anesthesiology and Medicine, Baylor College of
Medicine, Houston, TX 77030
APStracts 3:0386H, 1996.
Evidence for an H+,K+-ATPase (HKA) in vascular smooth muscle cells has
recently been demonstrated in rat aorta and a rat smooth muscle cell
line (A7r5) by functional studies. Our laboratory has used RT-PCR and
Northern hybridization techniques to define the type of HKA present
in canine whole carotid artery and confluent carotid artery cells.
PCR primers to detect an HKA message of unknown isoform were designed
based on homology to known sequences of gastric, colonic and toad
bladder HKA isoforms and dissimilarity to the Na+,K+-ATPase (NKA)
isoforms. A PCR product of predicted size was generated from cDNAs of
both confluent cells and whole vessel carotid artery which posses 91%
nucleotide sequence identity to the canine gastric HKA. Northern
hybridization using the PCR product as a probe revealed hybridization
to whole vessel carotid artery, cultured confluent carotid artery
cells, kidney, and stomach canine total RNA at the known message size
for the gastric HKA isoform. These data suggest that vascular smooth
muscle cells express an HKA mRNA which may be identical to the
gastric isoform.
Received 3 August 1995; accepted in final form 26 August 1996.
APS Manuscript Number H734-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 19 September 1996