Aims: 

Vitamin C is one of the most used vitamins, without clear evidence about direct effects on coronary flow. On the other hand, folic acid, has recently gained considerable attention because of its great potential to prevent many disorders, including endothelial dysfunction. For this purpose, the aim of this study was to assess the effects of Vitamin C and Folic acid on coronary flow (CF) and nitrite outflow (NO) alone or under inhibition of nitric oxide synthase in isolated rat heart.

Methods: 

The hearts of male Wistar albino rats (n = 12, 8 weeks, BM 180-200 g) were perfused according to Langendorff technique at constant perfusion pressure conditions (CPP, 40-120cm H₂O). The experiments were performed during control conditions, in the presence of: a) Vitamin C (100 mM) or Vitamin C plus L-NAME (30 mM) and b) Folic acid (100 mM) or Folic acid plus L-NAME. Results:

CF varied in autoregulatory range from 4.58 ± 0.52 to 6.13 ± 0.54 ml/min/g wt (50-90cm H₂O). Additionally, NO varied from 4.60 ± 0.42 to 6.52 ± 0.35 nmol/min/g wt and was parallel with CPP-CF curve. The autoregulatory range of CF was not significantly influenced by Vitamin C with parallel changes in NO (3.13 ± 0.48 - 8.37 ± 0.74 ml/min). Folic acid significantly increased CF (5.63 ± 0.10 - 15.2 ± 0.42 ml/min) accompanied by parallel changes in NO (2.28 ± 0.29 - 6.66 ± 0.50 nmol/min/g wt). L-NAME decreased Vitamin C-induced flow changes, but not folic-acid induced CF-changes. Completely opposite effects were showed on NO – Vitamin C effect was not significantly affected, while folic acid induced effects were additionally increased.

Conclusion: 

The results showed that applied vitamins have different effects on isolated rat heart and opposite interaction with NO-system.