Hypertension-induced changes of platelet-derived growth factor receptor expression in rat aorta and heart.
Hypertension-associated growth of vascular smooth muscle cells might be mediated in vivo by platelet-derived growth factor (PDGF). Our previous investigations in hypertensive rats failed to demonstrate changes in aortic steady-state mRNA levels of PDGF A or B chains. The current studies were performed to determine whether hypertension might affect the expression of PDGF receptors. We studied PDGF alpha- and beta-receptor gene expression by Northern analysis using human and rat cDNA probes. Studies of tissue distribution revealed that PDGF beta-receptor mRNA was most abundant in total aorta and aortic media, whereas the PDGF alpha-receptor mRNA was most abundant in the lung and was expressed at low levels in aortic tissue. Deoxycorticosterone acetate (DOCA)-salt hypertension induced a threefold increase in aortic steady-state PDGF beta-receptor mRNA levels. Aortic PDGF beta-receptor expression also was higher in spontaneously hypertensive rats (SHRs) when compared with age-matched normotensive Wistar-Kyoto (WKY) controls. Aortic PDGF alpha-receptor steady-state mRNA levels were unchanged in DOCA-salt hypertension and were expressed at similar levels in WKY rats and SHRs. Unlike the findings with aorta, cardiac PDGF beta- and alpha-receptor and PDGF B-chain expressions were unchanged in the DOCA-salt model and were decreased in SHRs. These findings indicate that hypertension can increase aortic steady-state mRNA levels for PDGF beta-receptor. They also indicate that tissue-specific expression of the genes of the PDGF ligand/receptor system are differentially regulated in hypertension.
Sarzani
R
R
Whitaker Cardiovascular Institute, Boston, Mass.
Arnaldi
G
G
Chobanian
A V
AV
D000818:Animals; D001011:Aorta / Q000378:metabolism*; D003900:Desoxycorticosterone; D006973:Hypertension / Q000139:chemically induced / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009392:Nephrectomy; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D011921:Rats, Inbred WKY; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D017479:Receptors, Platelet-Derived Growth Factor; D012965:Sodium Chloride
D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D003900:Desoxycorticosterone; D012965:Sodium Chloride; D017479:Receptors, Platelet-Derived Growth Factor