APOPTOSIS AND MORPHOMETRY OF THE GRANULOMATOUS LESIONS INDUCED BY THE Angiostrongylus vasorum IN DOGS

Angiostrongylus vasorum (Baillet, 1866) is a nematode of the Protostrongylidae family that inhabits the right side of the heart and the pulmonar artery of domestic dogs and other Canidea in different continents. Angiostrongylosis induces granuloma formation with variable volume and composition in different phases in lungs and in other organs. Lung fragments embedded in wax obtained from 12 mongrel dogs experimentally infected with larvae of A. vasorum were sectioned and stained with Hematoxiline Eosine and analyzed at light microscopy. Lesions were classified in mild, moderate and severe according to clinical history and morphological aspect. The following morphometric parameters were analyzed: granuloma area, number of larvae/eggs per area and apoptosis in granulomas and inside giant cells. Increase of number of larvae/eggs was proportional to increase in area and in intensity of the inflammatory reaction and to decrease in apoptosis. Giant cells were more frequent in moderated lesions and, when visible, most presented condensed or fragmented nuclei with evidence of apoptosis. Apoptosis were less frequent in severe lesions, when granulomas were the largest. It is possible that giant cells have a short life in angiostrongylosis.