Local Anesthetics for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is thought to be caused by an imbalance in the autonomic neurons of the colon. Researchers at the Uludag University School of Medicine in Turkey, led by Aysun Yilmazlar, professor in the Department of Anesthesiology and Reanimation, have taken this knowledge and used it in a study that reveals that local anesthetics may potentially reduce the inflammation at sites of the colon that are affected by IBD.

Yilmazlar and his team applied levobupivacaine, a novel, long-lasting topical anesthetic, onto the colonic mucosa of rats that had had experimentally induced IBD. With the use of a scoring system that compared the topical anesthetic to saline solution, the team observed some improvement in the degree of macroscopic inflammation at the areas where local anesthetics were applied.

According to the study published in the World Journal of Gastroenterology, the team induced colitis in 30 rats under general anesthesia with trinitrobenzene sulfonic acid and ethanol, while 10 rats were used as a sham group. Following the induction of colitis, the rats were further divided into three groups: “budesonide group received 0.1 mg/kg budesonide, levobupivacaine group received 10 mg/kg levobupivacaine and saline group received 1 mL saline solution via rectal route for 7 d.” According to the abstract, “at the end of 7 d, laparotomy and total colectomy were performed for histopathological examination in all rats and blood samples were drawn for measurement of tumor necrosis factor (TNF)-α and interleukin (IL)-6 following cardiac puncture.”

The study results reveal that “weight loss (P = 0.016) and macroscopic examination scores (P = 0.001) were significantly higher in saline group than others,” but histopathological scoring was comparable in all colitis groups (P = 0.350). The researchers did not observer any significant differences “in TNF-α levels and IL-6 levels (P = 0.150).”

The researchers conclude that, although the findings were not supported microscopically, “the significant improvement in macroscopic scores suggests that levobupivacaine may have topical anti-inflammatory effects in an experimental colitis model.”