D. Susic et al., Abnormal renal vascular responses to dipyridamole-induced vasodilation in spontaneously hypertensive rats, HYPERTENSIO, 37(3), 2001, pp. 894-897
Citations number
18
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
The objective of this study was to determine whether there were differences
in hemodynamic responses of different vascular beds to systemic administra
tion of dipyridamole between spontaneously hypertensive (SHR) and normotens
ive Wistar-Kyoto (WKY) rats. To this end, systemic hemodynamics and organ b
lood flows (using labeled microspheres) were determined in conscious rats b
efore and 10 minutes after dipyridamole (4 mg . kg(-1) . min(-1)) infusion.
In both the normotensive and hypertensive rats, the dipyridamole infusion
reduced arterial pressure by approximate to 20 mm Hg, associated with a dec
reased total peripheral resistance and an increased cardiac output. Renal b
lood flow decreased significantly in SHR after dipyridamole but remained un
changed or increased slightly in the WKY rats. There were no other differen
ces in regional hemodynamics, including those of brain, liver, skin, and mu
scle, between the WKY and SHR. Antihypertensive treatment completely restor
ed normal renal vascular response to dipyridamole. Previous reports had dem
onstrated an abnormal coronary hemodynamic response of the SHR. Our data de
monstrate that, as with coronary hemodynamics, hypertension selectively ind
uced alterations in renal vasculature. These findings may be of importance
in identifying the earliest hemodynamic evidence of developing hypertensive
nephrosclerosis.