The role of nitric oxide in regulation of leukocyte migration into the heart tissue in vitro

Abstract

Characteristics of leukocyte migration have been studied during the incubation of the right and left ventricles of rat heart explants in autologous blood plasma. Within the first 60 min, the leukocyte amount in the medium increases. Moreover, it is associated with cell release from the heart tissue. During further incubation, the cell release decreases; after 3 h of incubation, the cells begin to migrate back into the heart tissue. However, neutrophil migration does not change. Sodium nitrite, being a donor of nitric oxide significantly, reduces the leukocyte migration from the heart explants into the incubation medium, especially from left ventricle explants.

Flavonoid-enriched fraction from Echinodorus macrophyllus aqueous extract exhibits high in-vitro and in-vivo anti-inflammatory activity

“…Interestingly, it has been reported that NO induces PECAM‐1, VLA‐4 and Mac‐1 expression, thus accelerating the transendothelial migration of neutrophils, Also, animals treated with iNOS inhibitors or iNOS − / − mice show reduced neutrophil migration induced by carrageenan . However, the effects of NO are contradictory, suggesting that the importance of iNOS in modulating leucocyte recruitment can vary according to the type of inflammatory response . We can hypothesise that AEEm and Fr20 can be inhibiting NO production, which can be contributing to reducing inflammation signs on the vascular system and leucocyte migration into inflammatory site.…”

“…[48] However, the effects of NO are contradictory, suggesting that the importance of iNOS in modulating leucocyte recruitment can vary according to the type of inflammatory response. [45,48] We can hypothesise that AEEm and Fr20 can be inhibiting NO production, which can be contributing to reducing inflammation signs on the vascular system and leucocyte migration into inflammatory site.…”

“…Nitric oxide, a simple gas molecule, is synthesized from l ‐arginine and oxygen by nitric oxide synthase (NOS) in different cells, including endothelial and neuronal cells, and phagocytes (eNOS, nNOS and iNOS, respectively) . As NO mediates vasodilatation and vascular permeability, stimulates leucocyte migration and AEEm and its fractions altered these parameters, their effects on in‐vitro NO production were also evaluated. LPS stimulated the NO production (17.86 μ m ), according to the literature, and AEEm inhibited NO production just on 0.1 μg/ml, corroborating inhibition data by another macrophage cell line (J774) .…”