Development of a rat model of chronic lymphedema and evaluation of its morphofunctional characteristics

Aim: To develop a minimally invasive model of chronic lymphedema in the hind limb of rats by injecting a detergent solution into lymph nodes without performing lymph node dissection and to evaluate its morphofunctional characteristics.

Material and Methods. The experiment was conducted on 14 male outbred Wistar rats divided into experimental (n = 7) and control (n = 7) groups. In the experimental group, 0.3 mL of 3% lauromacrogol 400 was injected into the popliteal and inguinal lymph nodes of the left hind limb through small skin incisions without lymph node removal. The right limb served as an internal control. Assessment was performed on day 60: limb circumference was measured at 7 points, and histological examination was carried out (hematoxylin and eosin staining, Van Gieson staining).

Results. On day 60, the experimental group showed a statistically significant increase in the circumference of the left limb compared to the right limb (total increase: 2.4 ± 0.7 cm; p = 0.000074) and compared to the left limb of the control group (p < 0.05 at all measurement points). Histologically, signs of stage II–III chronic lymphedema were observed: epidermal thickening, interstitial edema, collagen fiber disorganization, lymphocyte-macrophage infiltration, adipocyte hypertrophy, and early fibrosis. The right limb of the experimental group and both limbs of the control group retained intact morphology.

Conclusion. A new minimally invasive model of chronic lymphedema in the rat hind limb has been developed with high reproducibility, morphological validity, and technical accessibility. It can be used to study the pathogenesis of fibrosis and adipogenesis in lymphedema, as well as to develop and evaluate new pharmacological approaches.

1. Kalinin R.E., Suchkov I.A., Maksaev D.A. Endothelial dysfunction in patients with secondary lymphedema and methods of its correction (literature review). Science of the young (Eruditio Juvenium). 2019;7(2):283–293. (In Russ.). https://doi.org/10.23888/HMJ201972283-293

2. Filina Yu.V., Feyskhanov A.K., Ibragimova A.R. et al. Cadherin EGF LAG Seven-Pass G-type Receptor 1 (CELSR1) in Primary Lymphedema. Journal of Venous Disorders. 2024;18(2):163–172. (In Russ.). https:// doi.org/10.17116/flebo202418021163

3. Rockson S.G. Lymphedema after breast cancer treatment. N Engl J Med. 2018;379(20):1937–1944. https://doi.org/10.1056/NEJMcp1803290

4. Hayes S.C., Janda M., Ward L.C. et al. Lymphedema following gynecological cancer: Results from a prospective, longitudinal cohort study on prevalence, incidence and risk factors. Gynecol Oncol. 2017;146(3):623–629. https://doi.org/10.1016/j.ygyno.2017.06.004

5. Decorte T., Cerckel M., Kheir G.B. et al. Risk factors for lower limb lymphedema after gynecological cancer treatment: a systematic review. Front Oncol. 2025;15:1561836. https://doi.org/10.3389/fonc.2025.1561836

6. Grada A.A., Phillips T.J. Lymphedema: Pathophysiology and clinical manifestations. J Am Acad Dermatol. 2017;77(6):1009–1020. https://doi.org/10.1016/j.jaad.2017.03.022

7. Rusznyák I., Földi M., Szabó G. Lymphatics and Lymph Circulation. 2nd ed. Oxford: Pergamon Press, 1967:704. eBook ISBN: 9781483185972

8. Lee-Donaldson L., Witte M.H., Bernas M. et al. Refinement of a rodent model of peripheral lymphedema. Lymphology. 1999;32(3):111–117. PMID: 10494523.

9. Kanter M., Slavin S., Kaplan W. An experimental model for chronic lymphedema. Plast. Reconstr. Surg. 1990;85(4):573–580. https://doi.org/10.1097/00006534-199004000-00006

10. Derkachev S.N., Kobzar I.G., Selimov Sh.V. et al. Evolution of Surgical Treatment Methods for Patients with Varicose Veins. I.P. Pavlov Russian Medical Biological Herald. 2025;33(4):599–610. https://doi.org/10.17816/PAVLOVJ686883. EDN: ZKNKAM

11. Azhar S.H., Lim H.Y., Tan B.K., Angeli V. The unresolved pathophysiology of lymphedema. Front Physiol. 2020;11:137. https://doi.org/10.3389/fphys.2020.00137

12. Li C.Y., Kataru R.P., Mehrara B.J. Histopathologic features of lymphedema: a molecular review. Int J Mol Sci. 2020;21(7):2546. https://doi.org/10.3390/ijms21072546

13. Sano M., Hirakawa S., Sasaki T. et al. Role of Subcutaneous Adipose Tissues in the Pathophysiology of Secondary Lymphedema. Lymphat Res Biol. 2022;20(6):593–599. https://doi.org/10.1089/lrb.2021.0054

14. Baytinger V.F., Sukhodolo I.V., Kurochkina O.S. et al. Morphological changes in the skin and subcutaneous tissue during the creation of an experimental model of lymphedema on the hind limb of a white rat. Issues of Reconstructive and Plastic Surgery. 2022;25(1):40–52. (In Russ.). https://doi.org/10.52581/1814-1471/80/05

15. Tabibiazar R., Cheung L., Han J. et al. Inflammatory manifestations of experimental lymphatic insufficiency. PLoS Med. 2006;3(7):e254. https://doi.org/10.1371/journal.pmed.0030254

16. Zampell J.C., Yan A., Elhadad S. et al. CD4(+) cells regulate fibrosis and lymphangiogenesis in response to lymphatic fluid stasis. PLoS One. 2012;7(11):e49940. https://doi.org/10.1371/journal.pone.0049940

17. Bowman C., Rockson S.G. The Role of Inflammation in Lymphedema: A Narrative Review of Pathogenesis and Opportunities for Therapeutic Intervention. Int. J. Mol. Sci. 2024;25(7):3907. https://doi.org/10.3390/ijms25073907