Effect of Hexasulfobutylated C₆₀ on the Isolated Aortic Ring of Guinea Pig

Abstract

The effects of hexasulfobutylated C₆₀ (FC₄S) and monomalonic acid C₆₀ (MMA C₆₀), the fullerene C₆₀ derivatives, on isolated endothelium-containing or endothelium-denuded aorta of guinea pig were studied pharmacologically in vitro. In the endothelium-containing preparation of the aortic rings, phenylephrine (PHE) elicited contracture and acetylcholine (ACh) elicited a relaxing effect on the PHE-precontracted preparation. In the PHE-precontracted preparation, MMA C₆₀ (10 µmol/l) did not elicit a relaxing effect on the PHE-precontracted preparation. However, MMA C₆₀ (10 µmol/l) significantly reduced the maximum response of the relaxation elicited by ACh. FC₄S itself significantly relaxed the PHE-precontracted aortic rings. ACh-induced relaxation in PHE-precontracted endothelium-containing strips of the aortic rings was significantly potentiated if pretreated with FC₄S (10 µmol/l). In the denuded aortic rings, FC₄S did not elicit the relaxing effect in the PHE-precontracted preparation. The relaxing effect of FC₄S on the PHE-precontracted preparation was not altered when superoxide dismutase (250 units/ml) was pretreated. However, the relaxing effect was reduced when N(G)-nitro-L-arginine methyl ester (L-NAME, 1 mmol/l) or methylene blue (1 µmol/l) was pretreated. These results demonstrated that the vasorelaxation effect of FC₄S on the PHE-precontracted aortic ring is partly dependent on the release of nitric oxide (NO) or an NO-derived substance from the vascular endothelium.

Modest vasomotor dysfunction induced by low doses of C60 fullerenes in apolipoprotein E knockout mice with different degree of atherosclerosis

“…However, besides the generation of superoxide anions other scavenging of NO could also impair vasorelaxation, and C 60 fullerenes may have more complicated mechanisms of action in this respect. For instance, it has been reported that hexasulfobutylated C 60 fullerenes potentiated the endothelium-dependent vasorelaxation in aorta segments from guinea pigs [ 34 ]. In addition, it has been reported that other derivatives of C 60 fullerenes (called C 3 - or D 3 - tris -malonyl-C 60 -fullerene) inhibited the activity of eNOS and C 3 - tris -malonyl C 60 fullerenes, which had the largest hydrophobic surface area, inhibited eNOS the most [ 35 ].…”

A New Isoquinolinone Derivative with Noble Vasorelaxation Activity

“…The thoracic aorta was rapidly removed and cleaned of connective tissue and adherent fat in oxygenated Krebs solution of the following composition (mmol/l): NaCl 117, KCl 5.9, CaCl 2 2.4, MgCl 2 1.2, d-glucose 11.8 and Tris 20.0 dissolved in distilled water (pH 7.4 at 37°C) [7]. The isolated artery was cut into rings approximately 5 mm long.…”

“…In the endothelium-denuded preparation, the endothelium was removed by gently rubbing the intimal surface with a fine stainless steel rod, and the functional loss of endothelial cells was confirmed by loss of the relaxation response to ACh (10 Ìmol/l) in PHE-precontracted aorta. The preparations were mounted vertically in an organ bath (1 ml capacity) and they were kept at 37 B 1°C continuously bubbled with 100% O 2 , and superfused with a physiological solution at a constant rate of about 2 ml/ min [7].…”

Prospects of C60 Fullerene Application as a Mean of Prevention and Correction of Ischemic-Reperfusion Injury in the Skeletal Muscle Tissue

“…С 60 -фулерени та їх похідні здатні захищати клітини (напри-клад, нейрони, клітини гепатоми, епітеліальні клі тини) від різноманітних токсинів [50][51][52][53][54].…”