CARTPT and diabetes mellitus: Previous studies have also described the changes in the population size of CART–positive enteric neurons under the impact of various pathological factors, including inflammation, nerve fiber damage, experimental diabetes, neoplastic processes, hypertension and various toxic substances (Apau et al., 2018; Huang et al., 2019; Rancière et al., 2019; Xu et al., 2019; Zhang et al., 2023).