Morphometric features of the structural organisation of rabbit large intestine crypts after colotomy using polycaprolactone thread modified with L-arginine

The study of the morphological characteristics of large intestine tissues sutured with various surgical threads under experimental conditions is highly relevant, timely, and holds significant promise for both theoretical and practical medicine, particularly in the field of paediatric abdominal surgery. The aim is to determine the morphometric parameters of the structural organization of large intestine crypts during experimental colotomy using polycaprolactone thread modified with L-arginine (PCL-MA). Materials and methods. The study was conducted on 35 sexually mature, non-purebred domestic rabbits aged 9-10 months, in accordance with all bioethical standards. The animals were divided into a control group (5 individuals) and an experimental group (30 individuals). In the control group, all stages of surgical access and sampling of intact caecal wall tissue were carried out. The rabbits in the experimental group underwent colotomy, followed by suturing of the large intestine with PCL-MA. To achieve the aim, histological, semi-thin serial sectioning, morphometric, and statistical methods were employed. Results. The study showed that when using PCL-MA sutures, due to L-arginine on its surface, the number and functioning of absorptive enterocytes are restored from the 21st day of the experiment. The reaction of goblet cells in the crypts contributes to the formation of a protective mucosal barrier, which is manifested in an increase in their number (from day 3rd to day 14th of the experiment) and the presence of a significant number of cells in the stage of degranulation. Restoration and normalization of the functions of mucosal exocrinocytes of the perivulnar area were observed after the 21st day of the experiment. Conclusions. Poorly differentiated cells located within the crypts play a key role in the regeneration of the large intestine following surgery, as their proliferation contributes to the restoration of the cellular pool. The application of PCL-MA sutures exerts a positive influence on the processes of differentiation and the formation of undifferentiated cells within the crypts. No conflict of interests was declared by the authors.