Participation of NO in the vasodilatory action of isoespintanol

ROJANO B; SCHINELLA G.; RINALDI G; MOSCA SM

VITAE

UNIV ANTIOQUIA

Lugar: Medellín ; Año: 2019 vol. 26 p. 78 - 83

0121-4004

Background: accumulating evidence suggests that natural compounds and specifically monoterpenesexert a vasodilator action. Objetive: to investigate the vascular effects of isoespintanol (2-isopropil-3,6-dimetoxi-5-metilfenol, ISO) monoterpene isolated from the leaves of Oxandra cf xylopioides. Methods:thoracic aortic rings isolated from Wistar rats were contracted with KCl 80 mM and then relaxed byexposure to Ca2+-free solution in absence and in presence of ISO 0.6 mg/mL. The force/tissue ratio (F/W)and the time to obtain 50% of relaxation (T-50) were used to assess the maximal contractile response andthe relaxation, respectively. To examine the participation of NO additional experiments were performedunder inhibition of nitric oxide synthase with L-NAME (L-NG-Nitroarginine methyl ester). Results:ISO significantly decreased the F/W ratio (257 ± 19 vs. 360 ± 18) and did not change T-50. In presenceof L-NAME the effects of ISO on contractile response was abolished. Conclusions: these resultsdemonstrate that ISO exerts a vasodilator effect through NO-dependent pathways and suggest that aninhibition of calcium influx could be the involved mechanism.