ABSTRACT
During its adaptation to parasitism T. pseudospiralis appears to have acquired the ability to modulate mammalian host response to infection by directly or indirectly altering the neuroendocrine function of the host. The aim of the present work was to study the histopathological and histochemical changes that may take place in the adrenal cortex during T. pseudospiralis infection and after modulating the course of the infection by administration of an immunostimulant drug, levamisole. Two experimental groups were studied: Group I, early muscle stage [26 days p.i.], group II, late muscle stage [50 days p.i.]. Each group was further subdivided into three equal subgroups: T. pseudospiralis infected mice, infected mice receiving Levamisole on the 6th day p.i., and infected mice receiving the drug on the 14th day p.i. The adrenal cortices of T. pseudospiralis infected mice in both early and late muscle stages of infection showed hyperplasia of the zona fasiculata, increased cytoplasmic fat vacuoles associated with increased activity of alpha esterase and succinic dehydrogenase enzymes. These changes were more pronounced in infected mice which received levamisole early on the 6th day p.i