Kazunari Tominaga1, Yoshiko Fujikawa2, Fumio Tanaka3, Noriko Kamata3, Hirokazu Yamagami3, Tetsuya Tanigawa3, Toshio Watanabe3, Yasuhiro Fujiwara3, Tetsuo Arakawa3. 1. Department of Gastroenterology, Osaka City University Graduate School of Medicine, Japan. Electronic address: tomy@med.osaka-cu.ac.jp. 2. Department of Gastroenterology, Osaka City University Graduate School of Medicine, Japan; SAMURAI GI Research Center, Osaka City University Graduate School of Medicine, Japan. 3. Department of Gastroenterology, Osaka City University Graduate School of Medicine, Japan.
Abstract
AIM: Enteric glial cells (EGCs) modulate colonic motility in a maternal separation model. We aimed to investigate structural changes in gastric EGC and gastric emptying as responses to maternal separation and acute adulthood stress in rats to elucidate the pathophysiological roles of gastric EGC. MAIN METHODS: As a chronic stress, we subjected male Wistar rats to 3h of maternal separation during postnatal days 2-14. As an acute adulthood stress (7weeks of age), we used the 8-h water-immersion method. We morphologically evaluated gastric EGCs using whole-mount longitudinal muscle-myenteric plexus preparations. We analyzed gastric emptying by the phenol red method. KEY FINDING: The area of EGC processes that apparently overlapped with neurons increased according to stress intensity (acute stress, 10.4%; maternal separation, 10.2%; maternal separation plus acute stress, 26.6%; control, 5.0%). Ratios of morphologically changed leaf-like processes to the total processes were 8.1%, acute stress; 10.3%, maternal separation; 4.0%, control. Ratio dramatically increased in the combined stress group (20.5%, p=0.026 vs. control). The mean bulging head area of leaf-like processes in the combined stress group was greater by 6.4μm(2) (control, 2.4μm(2); p=0.042). Gastric emptying in the maternal separation group was gradually delayed (104.1% at 7weeks, 66.7% at 17weeks, and 48.5% at 48weeks; p<0.05, respectively). Gastric emptying in the combined stress group tended to be delayed at 17weeks (45.7% vs. 81% in controls, p=0.066). SIGNIFICANCE: Gastric EGCs exhibited structural changes according to stress intensity, which may be associated with stress-induced dysfunction of the stomach.
AIM: Enteric glial cells (EGCs) modulate colonic motility in a maternal separation model. We aimed to investigate structural changes in gastric EGC and gastric emptying as responses to maternal separation and acute adulthood stress in rats to elucidate the pathophysiological roles of gastric EGC. MAIN METHODS: As a chronic stress, we subjected male Wistar rats to 3h of maternal separation during postnatal days 2-14. As an acute adulthood stress (7weeks of age), we used the 8-h water-immersion method. We morphologically evaluated gastric EGCs using whole-mount longitudinal muscle-myenteric plexus preparations. We analyzed gastric emptying by the phenol red method. KEY FINDING: The area of EGC processes that apparently overlapped with neurons increased according to stress intensity (acute stress, 10.4%; maternal separation, 10.2%; maternal separation plus acute stress, 26.6%; control, 5.0%). Ratios of morphologically changed leaf-like processes to the total processes were 8.1%, acute stress; 10.3%, maternal separation; 4.0%, control. Ratio dramatically increased in the combined stress group (20.5%, p=0.026 vs. control). The mean bulging head area of leaf-like processes in the combined stress group was greater by 6.4μm(2) (control, 2.4μm(2); p=0.042). Gastric emptying in the maternal separation group was gradually delayed (104.1% at 7weeks, 66.7% at 17weeks, and 48.5% at 48weeks; p<0.05, respectively). Gastric emptying in the combined stress group tended to be delayed at 17weeks (45.7% vs. 81% in controls, p=0.066). SIGNIFICANCE: Gastric EGCs exhibited structural changes according to stress intensity, which may be associated with stress-induced dysfunction of the stomach.
Authors: Jonathon L McClain; Elvio A Mazzotta; Nidia Maradiaga; Natalia Duque-Wilckens; Iveta Grants; Alfred J Robison; Fievos L Christofi; Adam J Moeser; Brian D Gulbransen Journal: Am J Physiol Gastrointest Liver Physiol Date: 2020-09-30 Impact factor: 4.052