Sex-related differences were observed not only in human but
also in experimental hypertension. The aim of our study was to
compare blood pressure (BP) of aged male and female
heterozygous transgenic rats (TGR) harboring Ren-2 mouse
gene, with their normotensive Hannover Sprague-Dawley
(HanSD) controls. At the age of 9 months, systolic (SBP) and
diastolic blood pressure (DBP) were measured by a direct
puncture of carotid artery in rats awaking from isoflurane
anesthesia. Thiobarbituric acid-reactive species (TBARS)
formation was monitored as indicator of lipid peroxidation
damage in heart, kidney and liver, whereas intracellular content
of reduced glutathione was determined in the same organs as
the main intracellular antioxidant. Furthermore, plasma
triglycerides and total cholesterol as well as high-density
lipoprotein (HDL) and low-density lipoprotein (LDL) fractions of
cholesterol were measured. As compared to HanSD rats, we
found significantly elevated BP only in male TGR (MAP: 123±1
vs. 171±5, SBP: 150±2 vs. 208±7, and DBP: 99±3 vs.
140±4 mm Hg), but not between TGR and HanSD females, which
were both normotensive. We also did not find any significant
differences in TBARS and reduced glutathione in the three above
mentioned organs as well as in plasma cholesterol or its HDL and
LDL fractions between transgene-negative HanSD and TGR
animals of either sex. However, we found significant sex
differences in TBARS, glutathione and plasma lipids in both rat
strains. Our results confirmed that aged TGR exhibit a marked
sexual BP dimorphism, which does not seem to be dependent on
oxidative stress or abnormal cholesterol metabolism.