Mc. Paredescarbajal et al., EFFECTS OF DIETARY SPIRULINA-MAXIMA ON ENDOTHELIUM-DEPENDENT VASOMOTOR RESPONSES OF RAT AORTIC RINGS, Life sciences, 61(15), 1997, pp. 211-219
Citations number
24
Categorie Soggetti
Biology,"Medicine, Research & Experimental","Pharmacology & Pharmacy
The aim of this study was to evaluate the effects of Spirulina maxima
on vasomotor responses of aorta rings from male Wistar rats fed on a p
urified diet. For this purpose, the animals (weighing 200-240 g) were
allocated randomly in two groups. One receiving purified control diet
(A) and the other receiving purified diet containing 5% Spirulina (B).
Purified diets were according to American Institute of Nutrition guid
elines and adjusted to Spirulina protein content. All animals were fed
(20 g/day/rat) during two weeks, receiving water ad libitum and 12 h.
light-dark cycles. Spirulina mat ima effects were evaluated by concen
tration-response (CR) curves of aorta rings with or without endotheliu
m to phenylephrine (PE), both in presence and absence of indomethacin
(Indom) or indomethacin plus L-NAME (Indom. + L-NAME), and to carbacho
l (CCh). Aorta rings with endothelium from group B showed, relative to
corresponding rings from group A: 1) a significant decrease in the ma
ximal tension developed in response to PE. 2) this decrease was revert
ed by Indom. 3) Indom. + L-NAME induced an additional increase in the
contractile responses to PE. 4) a significant shift to the left of the
CR curve to CCh. No significant differences were observed in the tens
ion developed in response to PE in rings without endothelium from eith
er group. These results suggest that Spirulina maxima may decrease vas
cular tone by increasing the synthesis and release of both a vasodilat
ing cyclooxygenase-dependent product of arachidonic acid and nitric ox
ide, as well as by decreasing the synthesis and release of st vasocons
tricting eicosanoid from the endothelial cells. (C) 1997 Elsevier Scie
nce Inc.