Histopathological changes induced by the venom of the snake Vipera raddei (Armenian adder).

The venom of the Armenian adder (Vipera raddei Boettger, 1890) was tested for its ability to induce histopathological changes in rabbits after long-term (once every 6 days for 30 days) intramuscular injection of the venom (0.35 mg/kg approx. 0.5 LD 50), by light microscopic examination of some organs (liver, heart, kidney, adrenal, lung, spleen). V. raddei (Vr) venom induces changes including necrosis and edematous appearance with cellular infiltration and vacuolation. The injury of kidneys includes significant changes of the glomerular apparatus. Lung sections showed infiltration of erythrocytes within bronchial alveoli and dilation of bronchi. Liver sections showed vascular damage, significant quantities of hemosiderin and also presence of lymphohistiocyte elements. In the heart, Armenian adder venom produced slight disruption of the structure of cardiomyocytes, fibrosis and congestion of blood vessels. The histological structure of the spleen was not disturbed by the venom but there were lymphoblasts and numerous polynuclear macrophages within the central zone of follicules, which may indicate a development of moderate inflammatory reactions and activation of the complement system. Our results suggest that the venom of V. raddei induces moderate histopathological changes in vital organs.