INFLUENCE OF PRESSURE-OVERLOAD AND ACE-INHIBITOR THERAPY ON CONSTITUTIVE PROTEIN MESSENGER-RNA EXPRESSION IN THE SPONTANEOUSLY HYPERTENSIVERAT

Despite use as constitutive protein standards to quantify mRNA, data a re limited regarding alteration of cyclophilin or glyceraldehyde-3-pho sphate dehydrogenase (G3PDH) in hypertension or angiotensin converting enzyme (ACE) inhibitor treatment. We assessed these standards in 6 mo nth old Wistar-Kyoto rats (WKY, n = 16), compared to age-matched spont aneously hypertensive rats (SHR, n = 14). Additional SHR (n = 8) had r eceived enalapril for 3 to 4 months at evaluation. Left ventricular (L V) and kidney RNA was extracted for dot blot cyclophilin and G3PDH cDN A hybridization. Cyclophilin and G3PDH mRNA densitometries were expres sed as a ratio. Cyclophilin/G3PDH for the WKY, untreated SHR, and enal april SHR were 1.56 +/- 0.33, 1.45 +/- 0.42, and 1.49 +/- 0.51, respec tively, for the LV, and 1.52 +/- 0.09, 1.43 +/- 0.22 and 1.38 +/- 0.22 , respectively, for the kidney. Differences were not significant. Rela tive expression of cyclophilin/G3PDH was unaffected by genetic SHR hyp ertension, or long term enalapril. Thus, either constitutive mRNA may be confidently used to index structural or functional protein response s, at the transcriptional level, in the SHR.