MALARIA PARASITE

Plasmodium berghei, a rodent malaria parasite, is widely utilized in experimental models to investigate malaria-induced pathology. This study evaluated the histopathological effects of graded parasitemia on cardiac tissues of albino rats. Sixteen (n = 16) adult female albino rats weighing 130–174 g were randomly assigned into four groups (n = 4 per group): a control group (uninfected) and three treatment groups inoculated intraperitoneally with low (~1 × 10²), medium (~1 × 10⁴), and high (~1 × 10⁶) concentrations of parasitized red blood cells (iRBCs). The animals were housed under standard conditions at the University of Benin Histopathology Laboratory and observed for 42 days. At the end of the study, hearts were harvested, fixed in 10% neutral buffered formalin, processed, and stained with hematoxylin and eosin for histopathological analysis. The results showed that across all treatment groups, cardiac myocytes retained normal histological features, including peripherally placed nuclei, abundant eosinophilic cytoplasm, striated fibers, and intact intercalated discs. No evidence of necrosis, vacuolation, fibrosis, or inflammatory cell infiltration was observed in the myocardium. Morphometric analysis of body and organ weights revealed no significant differences in initial weight (p = 0.706), final weight (p = 0.553), or heart weight (p = 0.939) between groups. These findings suggest that P. berghei infection, within the experimental timeframe and across the administered parasite concentrations, does not produce overt histopathological or morphometric alterations in the cardiac tissue of Wistar rats. Further studies incorporating molecular and functional assessments are recommended to explore potential subclinical or biochemical cardiac effects of malaria parasitemia