Comparative Anatomy of Pancreas Across Animal Species: A Systematic Review

BACKGROUND: Animal models have been valuable tools for studying pathophysiology and testing novel therapeutic interventions for various pancreatic disorders. A comprehensive understanding of the anatomy of the pancreas in different animal species is essential for appropriate model selection for research applications. However, there is a scarcity of literature that systematically compares pancreatic anatomy across different animal species. METHODS: A comprehensive search of Embase, PubMed, and Biosis Preview databases was conducted from inception to March 2024 to identify full-text manuscripts that described the anatomy of the pancreas in various vertebrate animal classes. Established systematic review methods were followed for screening and data extraction. RESULTS: Seventy-two eligible studies were found in the literature search. The extracted data was organized into sections delineating the gross anatomy of the pancreas, pancreatic ducts, and histologic characteristics. An evolutionary trend in the organization of the pancreatic exocrine tissue was noted with a transition from a diffuse or dispersed form in primitive fish to a more compact configuration in higher vertebrate taxonomic levels. Similar trends were noted in the development of pancreatic ducts. The organization of the endocrine tissue of the pancreas varies significantly from species to species. CONCLUSION: This comparative review highlights the structural and histologic organization of the pancreatic tissue across animal species. This review offers a key resource for translational researchers seeking to develop animal models to recapitulate the spectrum of pancreatic disorders observed in human patients.