TY - JOUR
T1 - AE anion exchanger mRNA and protein expression in vascular smooth muscle cells, aorta, and renal microvessels
AU - Brosius, Frank C.
AU - Pisoni, Ronald L.
AU - Cao, Xinan
AU - Deshmukh, Gayatri
AU - Yannoukakos, Drakoulis
AU - Stuart-Tilley, Alan K.
AU - Haller, Christlieb
AU - Alper, Seth L.
PY - 1997/12
Y1 - 1997/12
N2 - Intracellular pH (pH(i)) is an important regulator of vascular smooth muscle cell (VSMC) tone, contractility, and intracellular Ca2+ concentration. Among the multiple transport processes that regulate VSMC phi, Na+-independent Cl-/HCO3/exchange is the major process that acidities VSMCs in response to an alkaline load. Here, we characterize, in native and cultured VSMCs, the expression of the AE family of band 3-related anion exchangers, the best studied of these Cl-/HCO3/- exchangers. A 4.2-kb AE2 mRNA was present in aorta and in all cultured VSMCs tested. Cultured VSMCs and aorta both expressed a ~165-kDaAE2 polypeptide, but a ~115-kDa polypeptide was the major AE2-related protein in aorta. AE3 mRNA levels in VSMCs and in arterial tissue were significantly lower than those for AE2, but AE3 or related polypeptides were readily detected by immunoblot and immunolocalization experiments. The ~125-kDa AE3 polypeptide was present in an immortalized aortic VSMC line, but the predominant AE3 epitope in aorta and most cultured cells was associated with a polypeptide of Mr ~80 kDa. These data demonstrate the expression in native arteries and in VSMCs of products of the AE2 and AE3 genes, which may contribute to Na+-independent Cl-/HCO3/- exchange activity in these tissues and cells.
AB - Intracellular pH (pH(i)) is an important regulator of vascular smooth muscle cell (VSMC) tone, contractility, and intracellular Ca2+ concentration. Among the multiple transport processes that regulate VSMC phi, Na+-independent Cl-/HCO3/exchange is the major process that acidities VSMCs in response to an alkaline load. Here, we characterize, in native and cultured VSMCs, the expression of the AE family of band 3-related anion exchangers, the best studied of these Cl-/HCO3/- exchangers. A 4.2-kb AE2 mRNA was present in aorta and in all cultured VSMCs tested. Cultured VSMCs and aorta both expressed a ~165-kDaAE2 polypeptide, but a ~115-kDa polypeptide was the major AE2-related protein in aorta. AE3 mRNA levels in VSMCs and in arterial tissue were significantly lower than those for AE2, but AE3 or related polypeptides were readily detected by immunoblot and immunolocalization experiments. The ~125-kDa AE3 polypeptide was present in an immortalized aortic VSMC line, but the predominant AE3 epitope in aorta and most cultured cells was associated with a polypeptide of Mr ~80 kDa. These data demonstrate the expression in native arteries and in VSMCs of products of the AE2 and AE3 genes, which may contribute to Na+-independent Cl-/HCO3/- exchange activity in these tissues and cells.
KW - Bicarbonate
KW - Chloride
KW - Intracellular hydrogen ion concentration
KW - Vascular smooth muscle
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U2 - 10.1152/ajprenal.1997.273.6.f1039
DO - 10.1152/ajprenal.1997.273.6.f1039
M3 - Article
C2 - 9435694
AN - SCOPUS:0031426999
SN - 0363-6127
VL - 273
SP - F1039-F1047
JO - American Journal of Physiology - Renal Physiology
JF - American Journal of Physiology - Renal Physiology
IS - 6 42-6
ER -