A Novel Laryngopharyngeal Reflux Disease Model for Bama Pigs

Qingyang Shi; Yuguang Wang; Jiahui Zhou; Xueshi Li; Yixin Zhao; Lihong Zhang; Liming Zhang

doi:10.1016/j.jvoice.2024.02.001

A Novel Laryngopharyngeal Reflux Disease Model for Bama Pigs

J Voice. 2024 Feb 29:S0892-1997(24)00022-5. doi: 10.1016/j.jvoice.2024.02.001. Online ahead of print.

Authors

Qingyang Shi¹, Yuguang Wang¹, Jiahui Zhou¹, Xueshi Li¹, Yixin Zhao¹, Lihong Zhang², Liming Zhang³

Affiliations

¹ Department of Otorhinolaryngology, Head and Neck Surgery, Peking University People's Hospital, Beijing, China.
² Department of Otorhinolaryngology, Head and Neck Surgery, Peking University People's Hospital, Beijing, China. Electronic address: zhang_li_hong@sina.cn.
³ Endoscopy Center, Peking University People's Hospital, Beijing, China.

PMID: 38429118
DOI: 10.1016/j.jvoice.2024.02.001

Abstract

Objective: To develop a novel Laryngopharyngeal Reflux Disease (LPRD) model in Bama pigs through endoscopic cricopharyngeal myotomy.

Methods: A total of eight 8-month-old Bama pigs were randomly assigned to either the control or surgery group. Prior to intervention, upper esophageal sphincter (UES) manometry and laryngopharyngeal Dx-pH monitoring were conducted to establish baseline physiological parameters for each pig. Subsequently, the surgery group underwent endoscopic cricopharyngeal myotomy, while the control group did not. Two weeks postintervention, these procedures were repeated to evaluate changes in UES contractility and the occurrence of reflux events. At week eight postsurgery, mucosal tissues from both groups were harvested for histological analysis. Hematoxylin and eosin (H&E) staining was used to assess inflammation, while transmission electron microscopy (TEM) examined alterations in intercellular spaces and desmosomes.

Results: The mean UES pressures in the control and surgery groups were 59 ± 9 mmHg and 68 ± 12 mmHg, respectively. In the surgery group, there was a significant decrease in UES pressure 2weeks after the operation compared to preoperative values (P = 0.005), whereas no significant change was observed in the control group (P = 0.488). Laryngopharyngeal reflux (LPR) was successfully induced in the surgery group as evidenced by reflux events with pH <5.0, which were not detected in the control group. HE staining revealed marked inflammatory cell infiltration and submucosal gland expansion in throat tissues of the surgery group Bama pigs. TEM further showed enlarged intercellular spaces and reduced desmosome numbers in the laryngopharyngeal epithelium compared to controls.

Conclusion: Given analogous throat epithelial structures to humans, Bama pigs are an appropriate species for an LPRD animal model. Endoscopic cricopharyngeal myotomy effectively induces LPR and observable pathological changes in Bama pigs, providing a valuable platform for further research into LPRD pathophysiology.

Keywords: Bama pig; Endoscopic cricopharyngeal myotomy; Inflammation; LPRD; UES.