ISSN 2415-3060 (print), ISSN 2522-4972 (online)
  • 3 of 45
УЖМБС 2023, 8(1): 22–29
Medicine. Reviews

The Greater Omentum of White Rats: Structural and Functional Characteristics and its Role in Peritonitis

Maksymenko O. S., Hryn V. H.

The greater omentum is now recognized as an important organ in the fight against intra-abdominal infections, so it is often called the “policeman of the peritoneal cavity”. The greater omentum plays the most important role in the implementation of immune supervision of the antigenic condition of the peritoneal fluid and rapid response of damage to the gastrointestinal tract, which is often complicated by inflammation of the peritoneum – peritonitis. The purpose of the work was to study the peculiarities of the structure of the greater omentum of white rats and its role in peritonitis by means of a bibliographic analysis of the literature. Materials and methods. This bibliographic analysis is based on published articles, books, textbooks, monographs and dissertation abstracts. For the purposes of this systematic review, a literature search was carried out in the worldwide Internet, domestic sources of literature, scientific and electronic library of Poltava State Medical University using the following key words: “morphology”, “comparative anatomy”, “greater omentum”, “greater omentum of the rats”, “immune system”, “white rats”, “laboratory animals”, “rat anatomy”, “peritonitis”. Results and discussion. The greater omentum of white rats and humans are represented by two different structures: translucent membranous regions and regions rich in adipose tissue. According to the literature, the greater omentum of white rats is the main morphological characteristic (in miniature), homologous to the human one. The main function of the greater omentum, according to the opinion of many authors and ours too, is immunity. Immune structures of the greater omentum of white rats are represented by lymphoid nodules, known in the literature as milky spots, most of which are located near arteries and veins. In pathological conditions, the greater omentum acquires absolutely special properties, such as plasticity, the ability to fuse with a traumatic and inflamed surface, the ability to hemostasis and phagocytosis, the ability to germinate and revascularize, to absorb fluids and microparticles from the peritoneal cavity, and the ability to the immunological response. Conclusion. According to the literature, the greater omentum of white rats is a miniature likeness of the greater omentum of a person. However, unlike the latter, it consists of only one duplication of the visceral peritoneum, between the leaves of which there are blood vessels with deposits of adipose tissue and milk spots. Thus, the greater omentum of white rats is a perfectly acceptable object of experimental research with the subsequent legitimate extrapolation of their results to humans. The greater omentum occupies a central place in the peritoneal defense mechanisms due to its innate immune function, high absorbing capacity, and ability to attach to neighboring structures to close defects of abdominal organs and promote their healing, due to its expressive angiogenic activity

Keywords: greater omentum, milky spots, peritonitis, white rats

Full text: PDF (Ukr) 422K

  1. Westenfelder C. Does the greater omentum ("policeman of the abdomen") possess therapeutic utility in CKD? J Am Soc Nephrol. 2014;25(6):1133-5. PMID: 24627351. PMCID: PMC4033388.
  2. Meza-Perez S, Randall TD. Immunological Functions of the Omentum. Trends Immunol. 2017;38(7):526-36 PMID: 28579319. PMCID: PMC5812451.
  3. Iizuka T, Ono M, Yamazaki R, Kagami K, Mitani Y, Sakai S, et al. Wavy Floating Greater Omentum Findings Are Useful for Differentiating the Etiology of Fetal Ascites. Diagnostics. 2021;11(2):326. PMID: 33671226 PMCID: PMC7922392.
  4. Di Nicola V. Omentum a powerful biological source in regenerative surgery. Regen Ther. 2019;11:182-91. PMID: 31453273. PMCID: PMC6700267.
  5. Liu J, Geng X, Li Y. Milky spots: omental functional units and hotbeds for peritoneal cancer metastasis. Tumor Biol. 2016;37(5):5715-26. PMID: 26831659. PMCID: PMC4875158.
  6. Wang AW, Prieto JM, Cauvi DM, Bickler SW, De Maio A. The Greater Omentum-A Vibrant and Enigmatic Immunologic Organ Involved in Injury and Infection Resolution. Shock. 2020;53(4):384-90. PMID: 31389904. PMCID: PMC7000303.
  7. Ignjatović M. [Morphology and vascularization of the greater omentum]. Vojnosanit pregl. 1997;54(4):311-20. [Serbian]. PMID: 9441499
  8. Cleypool CGJ, Schurink B, van der Horst DEM, Bleys R. Sympathetic nerve tissue in milky spots of the human greater omentum. J Aat. 2020;236(1):156-64. PMID: 31498441. PMCID: PMC6904595.
  9. Luo X, Li L, Ou S, Zeng Z, Chen Z. Risk Factors for Mortality in Abdominal Infection Patients in ICU: A Retrospective Study From 2011 to 2018. Front Med (Lausanne). 2022 Feb 25;9:839284. PMID: 35280866. PMCID: PMC8916228.
  10. Ouf T, Jumuah WA, Mahmoud MA, Abdelbaset RI. Mortality rate in patients with Secondary Peritonitis in Ain Shams University Hospitals as regard Mannheim Peritonitis Index (MPI) score. QJM: An Int J Med. 2020;113(1):i111.
  11. Singer M, Deutschman CS, Seymour CW, Shankar-Hari M, Annane D, Bauer M, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-10. PMID: 26903338. PMCID: PMC4968574.
  12. Bilgiç T, İnce Ü, Narter F. Autologous omentum transposition for regeneration of a renal injury model in rats. Mil Med Res. 2022;9(1):1. PMID: 34983664 PMCID: PMC8725455.
  13. Silva PC, Jamel N, Refinetti RA, Manso EF, Schanaider A. [Development of blood vessels of the greater omentum in the hepatic lobe after vascular ligation. An experimental model in the rats]. Acta Cirurgica Brasil. 2006;21(6):416-21. PMID: 17160255.
  14. Wilkosz S, Ireland G, Khwaja N, Walker M, Butt R, de Giorgio-Miller A, et al. A comparative study of the structure of human and murine greater omentum. Anat Embryol. 2005;209(3):251-61. PMID: 15662530.
  15. Hryn VH, Kostylenko YP, Bilash VP, Tarasenko YA. Features of angioarchitecture of the albino rats stomach and small intestine. Wiad Lek. 2019;72(3):311-7.
  16. Hryn VH, Kostylenko YP, Bilash VP, Ryabushko OB. Microscopic structure of albino rats' small intestine. Wiad Lek. 2019;72(5 cz 1):733-8. PMID: 31175762.
  17. Hryn V, Kostylenko Y, Yachmin A. Features of white rats stomach anatomical structure. World Med Biol. 2019;15(67):133-7.
  18. Hryn V. [Features of the histological structure of the albino rat cecum]. Zh Med. 2019;17(3):296-302.
  19. Hryn V. Macro-microscopic features of the relief of the mucous membrane of the gastrointestinal tract of white rats. World Med Biol. 2019;15(70):188-93.
  20. Hryn V. Zahalʹna anatomichna kharakterystyka tonkoyi kyshky bilykh shchuriv [General anatomical characteristics of small intestine in white rats]. APMM. 2018;18(4):88-93. [Ukrainian].
  21. Hryn VH, Kostylenko YP, Yushchenko YP, Ryabushko MM, Lavrenko DO. Comparative histological structure of the gastrointestinal mucosa in human and white rat: a bibliographic analysis. Wiad Lek. 2018;71(7):1398-403.
  22. Hryn VH, Kostylenko YP, Yushchenko YP, Lavrenko AV, Ryabushko OB. General comparative anatomy of human and white rat digestive systems: a bibliographic analysis. Wiad Lek. 2018;71(8):1599-602.
  23. Suzuki D, Kim JH, Shibata S, Murakami G, Rodríguez-Vázquez JF. Topographical anatomy of the greater omentum and transverse mesocolon: a study using human fetuses. Anat Cell Biol. 2019;52(4):443-54. PMID: 31949984 PMCID: PMC6952700.
  24. Liebermann-Meffert D. The greater omentum. Anatomy, embryology, and surgical applications. Surg Clinics North Am. 2000;80(1):275-93. PMID: 10685153.
  25. Liu JY, Yuan JP, Geng XF, Qu AP, Li Y. Morphological study and comprehensive cellular constituents of milky spots in the human omentum. Int J Clin Exp Pathol. 2015;8(10):12877-84.
  26. Rangel-Moreno J, Moyron-Quiroz JE, Carragher DM, Kusser K, Hartson L, Moquin A, et al. Omental milky spots develop in the absence of lymphoid tissue-inducer cells and support B and T cell responses to peritoneal antigens. Immunity. 2009;30(5):731-43. PMID: 19427241. PMCID: PMC2754314.
  27. Maksymenko O, Hryn V, Kostylenko Y. Zahalʹnyy plan budovy ta pryntsypy morfometrychnoho analizu velykoho cheptsya bilykh shchuriv [General plan of the structure and principles of morphometric analysis of the greater omentum of white rats]. APMM. 2022;22(1):105-10. [Ukrainian].
  28. Vdoviaková K, Petrovová E, Maloveská M, Krešáková L, Teleky J, Elias MZ, et al. Surgical Anatomy of the Gastrointestinal Tract and Its Vasculature in the Laboratory Rat. Gastroenterol Res Pract. 2016;2016:2632368. PMID: 26819602. PMCID: PMC4706906.
  29. Liu M, Silva-Sanchez A, Randall TD, Meza-Perez S. Specialized immune responses in the peritoneal cavity and omentum. J Leukocyte Biol. 2021;109(4):717-29. PMID: 32881077. PMCID: PMC7921210.
  30. Schurink B, Cleypool CGJ, Bleys RLAW. A rapid and simple method for visualizing milky spots in large fixed tissue samples of the human greater omentum. Biotechn Histochem. 2019;94(6):429-34. PMID: 30896309.
  31. Maksymenko O. Strukturna orhanizatsiya sudynnozhyrovykh arkad velykoho cheptsya bilykh shchuriv [Structural organization of the vascular-fatty arcades of the greater omentum of white rats]. Morphologia. 2022;16(3):61-8. [Ukrainian].
  32. Pinho Mde F, Hurtado SP, El-Cheikh MC, Rossi MI, Dutra HS, Borojevic R. Myelopoiesis in the omentum of normal mice and during abdominal inflammatory processes. Cell Tiss Res. 2002;308(1):87-96. PMID: 12012208.
  33. Hryn VH, Drabovskiy VS, Sytnik DA, Ryabuschko RM, Riabuschko MM, Bilash SM, et al. Peculiarities Of Morphoetiopathogenesis Of Acute Appendicitis And Consequences After Appendectomy. Wiad Lek. 2022;75(6):1492-9. PMID: 35907222.
  34. Clements TW, Tolonen M, Ball CG, Kirkpatrick AW. Secondary Peritonitis and Intra-Abdominal Sepsis: An Increasingly Global Disease in Search of Better Systemic Therapies. Scand J Surg. 2021;110(2):139-49. PMID: 33406974.
  35. Droniak MM. Changes of non-specific resistance in patients with postoperative peritonitis with abdominal sepsis. J Educ Health Sport. 2021;11(3):231-8.
  36. Svintsitskaya N, Hryn V, Katsenko A. Anatomy of the Urinary and Reproductive Systems. Structural Features in Childhood. Abnormalities. Vinnytsa: Nova Knyha; 2021.
  37. Fang H, Gong C, Fu J, Liu X, Bi H, Cheng Y, et al. Evaluation of 2 Rat Models for Sepsis Developed by Improved Cecal Ligation/Puncture or Feces Intraperitoneal-Injection. Med Sci Monitor. 2020;26:e919054.
  38. Lee MJ, Kim K, Jo YH, Lee JH, Hwang JE. Dose-dependent mortality and organ injury in a cecal slurry peritonitis model. J Surg Res. 2016;206(2):427-34. PMID: 27884339.
  39. Liu X, Wang N, Wei G, Fan S, Lu Y, Zhu Y, et al. Consistency and pathophysiological characterization of a rat polymicrobial sepsis model via the improved cecal ligation and puncture surgery. Int Immunopharmacol. 2016;32:66-75. PMID: 26802602.
  40. Utiger JM, Glas M, Levis A, Prazak J, Haenggi M. Description of a rat model of polymicrobial abdominal sepsis mimicking human colon perforation. BMC Res Notes. 2021;14(1):14. PMID: 33413600. PMCID: PMC7790355.
  41. Liu Y, Hu J-n, Luo N, Zhao J, Liu S-c, Ma T, et al. The Essential Involvement of the Omentum in the Peritoneal Defensive Mechanisms During Intra-Abdominal Sepsis. Front Immunol. 2021 Mar 18;12:631609. PMID: 33815381. PMCID: PMC8012523.
  42. Wang ZB, Li M, Li JC. Recent advances in the research of lymphatic stomata. Anatom Record (Hoboken, NJ : 2007). 2010;293(5):754-61. PMID: 20186966.
  43. Fedorko ME, Hirsch JG. Studies on transport of macromolecules and small particles across mesothelial cells of the mouse omentum. Morphologic aspects. Exp Cell Res. 1971;69(1):113-27. PMID: 4330918.
  44. Kawanishi K. Diverse properties of the mesothelial cells in health and disease. Pleura Peritoneum. 2016;1(2):79-89. PMID: 30911611. PMCID: PMC6386382.
  45. Sacchi G, Di Paolo N, Venezia F, Rossi A, Nicolai GA, Garosi G. Possible role of milky spots in mesothelial transplantation. Int J Artif Organs. 2007;30(6):520-6. PMID: 17628853.
  46. Wijffels JF, Hendrickx RJ, Steenbergen JJ, Eestermans IL, Beelen RH. Milky spots in the mouse omentum may play an important role in the origin of peritoneal macrophages. Res Immunol. 1992;143(4):401-9 PMID: 1518954.
  47. Ren Y, Hua L, Meng X, Xiao Y, Hao X, Guo S, et al. Correlation of Surface Toll-Like Receptor 9 Expression with IL-17 Production in Neutrophils during Septic Peritonitis in Mice Induced by E. coli. Mediators Inflamm. 2016;2016:3296307. PMID: 27057095. PMCID: PMC4785266.
  48. Frydrych LM, Bian G, Fattahi F, Morris SB, O'Rourke RW, Lumeng CN, et al. GM-CSF Administration Improves Defects in Innate Immunity and Sepsis Survival in Obese Diabetic Mice. J Immunol. 2019;202(3):931-42. PMID: 30578307.
  49. Li Y, Karlin A, Loike JD, Silverstein SC. A critical concentration of neutrophils is required for effective bacterial killing in suspension. Proc Natl Acad Sci U S A. 2002;99(12):8289-94. PMID: 12060772. PMCID: PMC123060.
  50. Doherty NS, Griffiths RJ, Hakkinen JP, Scampoli DN, Milici AJ. Post-capillary venules in the "milky spots" of the greater omentum are the major site of plasma protein and leukocyte extravasation in rodent models of peritonitis. Inflamm Res. 1995;44(4):169-77. PMID: 7545527.
  51. Platell C, Cooper D, Papadimitriou JM, Hall JC. The omentum. World J Gastroenterol. 2000;6(2):169-76.