24, 25 have shown the LPS‐induced periodontitis in rats and reported the beneficial effects of treatment with methanandamide and cannabinoid‐2 receptor agonist, which may be useful for the oral health. Gurkan et al. 26 also used the rat experimental periodontitis induced by LPS and reported the therapeutic effects of vasoactive intestinal peptide by monitoring alveolar bone. This evidence concerns the gene VIP and periodontitis.