Spontaneous oscillations in intratubular pressure were more frequent in normotensive WKY rats than in spontaneously hypertensive rats (88% vs. 54%) and were abolished by furosemide.
Spontaneously hypertensive rats exhibit irregular, potentially chaotic oscillations in intratubular pressure compared to normotensive rats, though both depend on tubulo-glomerular feedback activity.
Tasa de eventos absoluta: 54% vs 88%
A highly sensitive oscillatory tubulo-glomerular feedback (TGF) response has previously been demonstrated in normotensive Sprague-Dawley rats. The purpose of the present study was to examine whether such as oscillating TGF-response could be elicited in Wistar-Kyoto rats (WKY) and genetically hypertensive rats (SHR) and furthermore if any differences in the TGF-response characteristics between SHR and WKY rats could be detected. The closed loop function of the TGF-system was studied. In 12-18-week-old WKY rats regular oscillations in the intratubular pressure occurred spontaneously. The median frequency were 29.7 mHz (range 20-46.7 mHz). In SHR rats, spontaneous oscillations also occurred, but these were highly irregular. Spontaneous oscillations were more frequent in WKY than in SHR (88% vs. 54%). In both strains, oscillations could be elicited by free flow microperfusion with artificial tubular fluid (ATF). When furosemide was added to the ATF in a concentration of 0.1 mM, the oscillations were abolished in both strains of rats. It is concluded that, in both strains of rats the oscillatory phenomena depend upon TGF activity. It is suggested that the irregular pattern of the oscillations observed only in SHR rats may represent a chaotic process.
Holstein‐Rathlou et al. (Sat,) conducted a other in Hypertension. Free flow microperfusion with artificial tubular fluid (ATF) and furosemide vs. WKY vs SHR rats was evaluated on Spontaneous oscillations in intratubular pressure. Spontaneous oscillations in intratubular pressure were more frequent in normotensive WKY rats than in spontaneously hypertensive rats (88% vs. 54%) and were abolished by furosemide.