Foundation. Chronic plantar fasciopathic pain syndrome is a pathology that significantly affects the quality of life of patients of all age categories. Insufficient knowledge of the etiological and pathogenetic factors in the development of fasciopathies explains the multiplicity, and sometimes inconsistency, of conservative and surgical treatment regimens. The choice of the optimal variant of therapeutic or surgical intervention may be associated with experimental modeling of fasciopathies and the study of the dynamics of the pathological process.The aim. To study the morphological changes in structures identical to the human plantar aponeurosis in experimental modeling of fasciopathy in animals.Research methods. The material for the study was fragments of the tendonaponeurotic complex of the foot of laboratory animals (control group: animals with the introduction of physiological sodium chloride solution (n = 12); main group: animals with the introduction of alprostadil (n = 12)). The methods of light microscopy (staining with alcian and toluidine blue, according to Van Gieson, Weigert – Van Gieson and Picro-Mallory) and morphometry were used.Results and discussion. As a result of the study, it was found that the four-fold administration of alprostadil had a significant effect on the structure of the dense fibrous connective tissue of the plantar foot of laboratory animals. The mechanisms of damage (edema, microhemorrhages, infiltration by lymphocytes, plasmocytes and leukocytes, dystrophy by the type of mucoid and fibrinoid swelling, delamination and rupture of collagen fibers), adaptation and regeneration (the appearance of a large number of activated fibrocytes, fibroblasts, microvessels, neoplasm of collagen fibers) were activated. All this together led to spatial focal histotopographic changes, consisting in an increase in the cellular composition of connective tissue structures against the background of a noticeable violation of their spatial orientation.Conclusion. Modeling of fasciopathy using alprostadil was accompanied by the appearance of mosaic reversible and irreversible heteromorphic and heterochronous changes in all connective tissue aponeurotic structures. Such histotopographic changes should be considered as one of the reasons for the clinical manifestations of plantar fasciopathies, causing functional insufficiency and explaining the clinical recurrent nature of the pathological process.