The effects of folic acid on vascular reactivity in a hyperhomocysteinemic rat model

Abstract Objective: This study aimed to investigate the antioxidant effects of folic acid and its effects on contraction and relaxation responses in rat aorta in hyperhomocysteinemic rats. Methods: Thirty-four male Wistar Albino rats were allocated into four groups. Rats in the hyperhomocysteinemia group (Group 1, n=9) received 1g/kg/day methionine via orogastric gavage for 30 days and then injected with intraperitoneal saline for the next 7 days. In the hyperhomocysteinemia+folic acid group (Group 2, n=9), following the administration of methionine for 30 days, folic acid (4mg/kg/day) was delivered intraperitoneally for 7 days. Sham group rats (Group 3, n=8) received orogastric saline for 30 days, which was followed by an IP injection of saline for another 7 days. Animals allocated into the folic acid group (Group 4, n= 7) had orogastric saline for 30 days and intraperitoneal folic acid for 7 days. After 5 weeks of treatment, blood samples were obtained, all animals were sacrificed, and hearts were harvested. Thoracic aortic segments were suspended on individual organ baths, and acetylcholine-induced (endothelium-dependent) relaxation responses of isolated aortic rings were evaluated. Results: Relaxation responses in Group 1 thru 4 were 73.889.96, 76.159.28, 76.618.83, and 69.2615.68, respectively. There was no significant difference in the organ bath in terms of relaxation response to acetylcholine at a dose of 10-9 mM between the groups (F=0.716, p=0.550). Conclusion: Folic acid therapy failed to produce a significant improvement in vascular reactivity. Keywords: Hyperhomocysteinemia, folic acid, vascular reactivity