HISTOLOGICAL AND MORPHOMETRIC CHANGES IN THE PULMONARY MICROVASCULATURE OF RATS ONE DAY AFTER ADMINISTRATION OF LEIURUS MACROCTENUS SCORPION VENOM

Authors:

Abstract:

One day after administration of Leiurus macroctenus venom, pronounced histological changes were observed in the pulmonary microvasculature of rats, characterized by altered vascular blood filling and remodeling of the vessel walls. The arterioles and venules demonstrated thickening of the tunica media and tunica adventitia, marked perivascular edema, and infiltration by round inflammatory cells. In some vessels, narrowing or partial collapse of the lumen was observed, while adjacent vessels in certain microscopic fields exhibited pronounced congestion and erythrocyte stasis. Perivascular hemorrhages were also detected in some areas of the pulmonary stroma. Morphometric analysis confirmed a consistent reduction in the internal diameter of all examined components of the microcirculatory bed. The most pronounced changes were observed in the capillaries, whose diameter decreased by 44.51 % (p=0.0019), followed by the arterioles and venules, whose diameters decreased by 35.61 % and 35.00 %, respectively (p=0.0002), compared with the control group. These findings indicate the development of pronounced disturbances in pulmonary microcirculation as early as the first day following exposure to Leiurus macroctenus scorpion venom.

Keywords:

pulmonary microvessels of laboratory rats micromorphometric changes one day after exposure to Leiurus macroctenus scorpion venom

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Publication:

«World of Medicine and Biology» Vol. 22 No. 97 (2026), pp. 176-180
UDC 616.514-037:572.087+612-071

DOI:

https://doi.org/10.26724/2079-8334-2026-3-97-176-180