Effect of clove and cinnamon extracts on experimental model of acute hematogenous pyelonephritis in albino rats: Immunopathological and antimicrobial study.

Recent studies showed prominent antimicrobial activity of some plant extracts on some pathogenic microorganisms so we evaluated antimicrobial activity of aqueous extracts of clove and cinnamon using the agar well diffusion method. An in vivo study was carried out on 40 adult healthy male albino rats divided into four groups: Group 1: negative control group (received intragastric saline solution daily); Group 2: injected with mixed bacterial suspension of S. aureus and E.coli as a model of pyelonephritis then received intragastric saline solution daily; Group 3: injected with the same dose of mixed bacterial suspension then received intragastric clove extract 500 mg/kg/day; and Group (4): injected with mixed bacterial suspension then received intragastric cinnamon 500 mg/kg/day. Five rats from each group were sacrificed after 1 and 4 weeks. Serum and blood samples were collected for lysozymes activity and nitric oxide production, lymphocyte transformation test, as well as counting of both total and differential leukocytes and erythrocytes. Kidney samples were tested histopathologically. Both in vivo and in vitro results confirmed the efficacy of clove extract as natural antimicrobials and suggested the possibility of its use in treatment of such bacterial infections.