Differences between in vitro and in vivo obtained schistosomules

Injecao de cercarias de Schistosoma mansoni na cavidade peritoneal de camundongos normais induz adesao celular a estas lavras. Esta aderencia diminui acentuadamente quando as lavras infectantes se transformam em esquistossomulos. Este procedimento foi usado para detectar diferencas entre esquitossomulos obtidos in vivo e in vitro. A reinoculacao de esquistossomulos obtidos in vivo na cavidade peritoneal de camundongos nao acarreta adesao celular. Por outro lado, celulas aderentes foram encontradas em esquistossomulos obtidos in vitro (4 e 24 horas, respectivamente). Nossos dados referentes a esquistossomulos obtidos in vitro indicam que mais de 24 horas sao necessarias para a completa remocao de moleculas envolvidas no fenomeno de adesao celular

Changes in choline acetyltransferase activity of rat tissues during Chagas' disease

1. The activity of choline acetyltransferase (CAT) measured by a radilabeling method was significantly reduced in the heart, submandibular gland and esophagus of rats 20 days after inoculation with Trypanosoma cruzi (Y strain). 2. Normal enzyme activity was recovered in all these organs 100 days after inoculation. 3. In the transcerse colon, no change, 30% reduction and normal activity were found at days 20, 100 and 430 of infection, respectively. 4. The data indicate recovery of parasympathetic function in experimental Chagas' disease. Axonal regrowth and sprouting are discussed as possible candidates for the recovery mechanisms