Chronic myocardial damage in experimental T. cruzi infection of a new world primate, Cebus sp. monkey

Abstract

Eighteen Cebus apella monkeys, (juvenile and adult of both sexes) were inoculated five years ago, with three Trypanosoma cruzi strains (CA1, n = 10; Colombian, n=4 and Tulahuen, n=4), either by conjunctival or intraperitoneal route, once or repeatedly. Parasitological, hematological, serological, enzymatic, radiographic, electro and echocardiographic findings have been peviously published15 and they are similar to those observed in human pathology. The most frequent electrocardiographic alteration was right branch bundle block. Six animals, chosen at random, were sacrificed. Those sacrificed 20 to 25 months post-first inoculation showed focal accumuli of leukocytes with myocytolysis. Foci of diffuse interstitial fibrosis with mild infiltrate of leukocytes among fibers were observed in the animals sacrificed 36 to 47 months post-inoculation. No parasites were seen. The lesions were more prominent in the ventricular walls and the septum. The fact that the infiltrates were predominant in the animals sacrificed at a shorter time after first inoculation and that fibrosis was more severe in those sacrificed at a longer time suggests that there is a progression of the infiltrative lesions to fibrosis, with a leukocytic activity indicative of a chronic phase. These lesions are similar to those described in human chronic Chagas' disease. This would demonstrate that this model is useful in evaluating a progress in the knowledge of the pathogenesis which is still a controversial issue, immunology, immunogenesis and chemotherapeutic agents of the chronic and indeterminate phases of this disease.

Dilative cardiomyopathy leading to congestive heart failure in a male squirrel monkey (Saimiri sciureus)

“…Cardiomyopathy in other species can occur spontaneously or result from an inflammatory response, a nutritional deficiency, or following the administration of a toxic agent. Infectious agents such as Trypanosoma cruzi can induce myocarditis and cardiomyopathy in New World and Old World nonhuman primates [7,10]. Viral mediated myocarditis can also lead to dilative cardiomyopathy in humans [1].…”

Valores de referência das provas de funções hepática, renal e de alguns eletrólitos em Cebus apella, anestesiados com cetamina

“…O macaco-prego (Cebus apella) representa uma das 37 espécies de primatas do Novo Mundo (MARTIN, 1986) e é freqüentemente utilizado como modelo biológico em estudos de zoonoses, como tuberculose (FAKLEN et al, 1983), doença de Chagas (FALASCA et al, 1990;MALCHIODI et al, 1993), além de experimentos nutricionais relacionados ao metabolismo de ácidos graxos saturados, níveis de colesterol e triglicérides, bem como suas conseqüências na agregação plaquetária (PRONKUK et al, 1991;DIVILLARD et al, 1992;KLOSLA & HAYES, 1992).…”

Clinical, biochemical, and electrocardiographic aspects of Trypanosoma cruzi infection in free‐ranging golden lion tamarins (Leontopithecus rosalia)

“…Sinus arrhythmia is a feature commonly observed in healthy primates [16, 37, 38] and humans [11]. Although both sinus tachycardia and bradycardia have been reported in monkeys experimentally infected with T. cruzi [4, 12, 24] there is no basis for speculation that this alteration has any clinical relevance in T. cruzi infected GLTs.…”

“…The array of electrocardiographic disturbances associated with T. cruzi infection in humans and experimentally infected primates includes depolarization/repolarization abnormalities and conduction disturbances. The latter includes complete or incomplete atrioventricular blocks and other conduction disturbances [6, 8, 12, 31, 39]. Absence of electrocardiograph (ECG) alterations or clinical symptoms in experimentally infected animals, as occurs in the undetermined phase of human Chagas’ disease, has also been reported [1, 10, 16, 18, 29].…”