Resumo

ACEVEDO, Luz Marina; FINOL, Héctor José  e  SUCRE, Luis. Patología UltraestructuraL del músculo gluteus medius de Caballos Criollos en los llanos venezolanos infectados naturalmente por el virus de la anemia infecciosa equina. Rev. Cient. (Maracaibo) [online]. 2009, vol.19, n.3, pp.268-276. ISSN 0798-2259.

The equine infectious anemia (EIA) is a viral disease of acute response and progress to chronic course which affects equine of Venezuelan plains. Until now, there is no information about the possible effect of EIA on skeletal muscle ultrastructure. The aim of the present investigation was to study the ultrastructure of muscle Gluteus medius from horses positive to Coggins test and animal control negative to the test. Muscle biopsies were processed by routine techniques for transmission electron microscopy. Muscle alterations varied from slight to severe, including atrophy, swelling of sarcotubular system and mitochondria. Mitochondria showed a matrix with different electron densities and the presence of electron dense granules. There were observed different kinds of lysosomes. More severe alterations included hypercontraction and complete loss of myofilaments, rupture of sarcolemma and segmental necrosis. Intramuscular capillaries exhibited endothelial cell cytoplasm infoldings into the lumen and partially or totally occluded lumen. Basement membrane was widened and reduplicated. Some capillaries showed widened endothelial cell cytoplasm, mitochondria and rough endoplasmic reticulum swelling and even degenerated. Others showed ruptured endothelial wall. Pericytes exhibited a cytoplasm which varied from normal to a proliferative one. The mononuclear cell infiltrate consisted of macrophages and neutrophils. Most of observed alterations have been described in muscle disorders with an autoimmune component.

Palavras-chave : Equine infectious anemia; skeletal muscle; ultrastructure.