[Effects of aspirin and nifedipine alone or in combination on mesenteric microcirculation of rats].
OBJECTIVE
To study the effects of the combination of aspirin (Asp) and nifedipine (Nif) on mesenteric microcirculation of rats.


METHODS
Acute microcirculation disturbance (AMD) was produced by high molecular weight dextran (M(r) 480,000, 360 mg.kg-1 i.v.). Arteriole and venule blood flow velocity and diameter (ABFV, VBFV, AD, VD) and blood flow state (BFS) were observed by intravital microcirculation method.


RESULTS
Asp 2.5, 5 mg.kg-1, Nif 0.05, 0.1 mg.kg-1, Asp + Nif (1 + 0.025), (2.5 + 0.05) mg.kg-1, i.v. had the significant increase of 11.1%, 31.3%, 18.5%, 19.3%, 30.5%, 39.8% of ABFV and 12.5%, 25.7%, 12.6%, 15.2%, 29.6%, 36.1% of VBFV respectively, the marked improvement of BFS, and the distinctive increase of 4.3%, 17.9%, 35.9%, 39.7%, 15.2%, 42.8% of AD and 2.2%, 4.2%, 26.2%, 27.4%, 3.4%, 28.9% of VD separately, and got a raise in the number of capillaries. Asp + Nif (1 + 0.025), 2.5 + 0.05) mg.kg-1 i.v. could reverse AMD.


CONCLUSIONS
Asp was superior to Nif in the increase of BFV, but Nif was superior to Asp in expansion of blood vessel. Asp in combination with Nif produced marked synergistic action and protection againist AMD.
Cardiovascular Research Laboratory, Baotou Medical College, China.
Y M
YM
Song
J M
JM
Qin
Z X
ZX
Li
S
S
Shi
D000818:Animals; D001241:Aspirin / Q000494:pharmacology*; D001783:Blood Flow Velocity / Q000187:drug effects; D004357:Drug Synergism; D005260:Female; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects*; D008833:Microcirculation / Q000187:drug effects; D009543:Nifedipine / Q000494:pharmacology*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology*
D010975:Platelet Aggregation Inhibitors; D014665:Vasodilator Agents; D009543:Nifedipine; D001241:Aspirin