The histopathological and immunological pattern of CBA mice infected with Leishmania amazonensis after treatment with pyrazole carbohydrazide derivatives

► Pyrazolic agents showed a therapeutic effect in mice infected with Leishmania amazonensis. ► Treated animals had lower levels of inflammatory infiltration and amastigotes forms. ► IL-4 was expressed at a lower level in the treated group. ► Increased levels of the specific anti-Leishmania IgG2a or IgG3 antibody subclass were observed in NO2Cl and BrNO2-treated group, respectively.