Fish Balistes capriscus skin extract-induced relaxation in mesenteric arterial bed of rat.
The vasorelaxing activity of the aqueous extract of fish Balistes capriscus skin (AEBc) on mesenteric arterial bed (MAB) of rats was studied. The bolus injections of AEBc (bolus of 5.1, 10.2, 20.5, and 41.1mg) significantly inhibited, in a concentration-dependent manner, the maximal contractile response induced by methoxamine (30 microM) in MAB. The vasodilatation action of AEBc is not mediated through beta-adrenoceptors or cyclo-oxigenase, since it was not affected by propranolol (20 microM) or diclofenac sodium (3 microM). The vasodilator response induced by subsequent addition of AEBc Balistes capriscus in bolus was significantly reduced in water infusion for endothelium removal. Treatment with an inhibitor of NO synthase (L-NAME, 10 microM) decreased AEBc effect. The guanylate cyclase inhibitor methylene blue (MB, 100 microM) had no significant effect on AEBc-induced vasodilatation. These results suggest that the vasorelaxing effect of AEBc is mediated by endothelium-dependent (NO/EDRF) and endothelium-independent neurally induced vasorelaxation from nonadrenergic and noncholinergic nerves (NO).
Cavalli
L S
LS
Departamento de Ciências Fisiológicas, Universidade Federal do Rio Grande, Rio Grande, Rua Eng. Alfredo Huch 475, Rio Grande, 96201-900, Brazil.
Possette
P L
PL
Schmidt
B
B
Kruel
C
C
Grando
M
M
Badiale Furlong
E
E
Cezar-Vaz
M R
MR
Barros
D M
DM
Muccillo-Baisch
A L
AL
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004008:Diclofenac / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects*; D008729:Methoxamine / Q000494:pharmacology; D008751:Methylene Blue / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000737:chemistry*; D023721:Tetraodontiformes / Q000502:physiology*; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000302:isolation & purification / Q000494:pharmacology*
D000319:Adrenergic beta-Antagonists; D016861:Cyclooxygenase Inhibitors; D014665:Vasodilator Agents; D004008:Diclofenac; D011433:Propranolol; D019001:Nitric Oxide Synthase; D008729:Methoxamine; D008751:Methylene Blue; D019331:NG-Nitroarginine Methyl Ester