Antihypertensive effects of D-polymannuronic sulfate and its related mechanisms in renovascular hypertensive rats.
OBJECTIVE
To investigate the antihypertensive effects of D-polymannuronic sulfate (DPS), a kind of sulfated polysaccharide, and the underlying mechanisms in renovascular hypertensive rats (RHR).


METHODS
Used two-kidney one clip (Goldblatt, 2-K 1C) method to produce RHR model. DPS was given i.v. or ig for 5 wk with the initiation of establishment of RHR. Serum nitric oxide (NO) was determined with NO kit; plasma angiotensin II (Ang II) and endothelin-1 (ET-1) were measured by radioimmumoassays.


RESULTS
In acute therapeutic experiments, DPS markedly reduced systolic blood pressure (SBP) and diastolic blood pressure (DBP) dose-dependently and decreased heart rate (HR) with reduction in arterial blood pressure. In the prophylactic experiments, DPS prevented the rise in SBP and DBP in a dose-dependent manner. The hypotensive potency of DPS 50 mg/kg is comparable to that of captopril (14 mg/kg). Moreover, DPS elevated serum NO contents and lowered plasma concentrations of Ang II and ET-1.


CONCLUSIONS
The antihypertensive activities of DPS might be involved both in increasing the generation of nitric oxide and in decreasing the production of angiotensin II and endothelin-1 in vivo.
Zhu
H B
HB
Department of Marine Pharmacology, Marine Drug and Food Institute, Ocean University of Qingdao, Qingdao 266003, China.
Geng
M Y
MY
Guan
H S
HS
Zhang
J T
JT
D000804:Angiotensin II / Q000097:blood; D000818:Animals; D000959:Antihypertensive Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D019332:Endothelin-1 / Q000097:blood; D006339:Heart Rate / Q000187:drug effects; D006603:Hexuronic Acids / Q000302:isolation & purification / Q000494:pharmacology*; D006978:Hypertension, Renovascular / Q000097:blood* / Q000503:physiopathology; D008297:Male; D009569:Nitric Oxide / Q000097:blood*; D000459:Phaeophyceae / Q000737:chemistry; D051381:Rats; D011921:Rats, Inbred WKY
D000959:Antihypertensive Agents; D019332:Endothelin-1; D006603:Hexuronic Acids; C437391:polymannuronic sulfate; D000804:Angiotensin II; D009569:Nitric Oxide