Research article

A HISTOLOGICAL MICROSCOPIC VIEW OF THE WHITE MOUSE BRAIN DOSED EXPERIMENTALLY WITH ESCHERICHIA COLI O157:H7 AND TREATED WITH A DRUG AND ANTIBIOTIC

Ateen Amer Hameed, Prof. Dr. Khulood Naji Rasheed, Prof. Dr. Hala Mohammed Majeed

Online First: December 22, 2022


The research is conducted to detect the pathogenicity of E. coli O157: H7 and know the effects of its experimental infection in the histological structure of the brain of male mice at the age of (8-12) weeks, In addition, it attempts to determine the therapeutic effect of an approved drug in the treatment of bacteria and compare it with an antibiotic whose effectiveness is tested in vitro. The antibiotic sensitivity test results show that the bacteria are sensitive to Trimethoprim-Sulfamethoxazole, Metronidazole, Gentamicin, Amikacin, Tetracycline, Azithromycin, Ceftriaxone and Ciprofloxacin, and resistant to Amoxicillin/clavulanic acid and Ampicillin. The most sensitive antibiotic is Ciprofloxacin, followed by Trimethoprim-Sulfamethoxazole. As the latter is an approved and widely used antibiotic, it is chosen with Ciprofloxacin to determine their therapeutic effect against the bacteria under study. Animals experimentally infected with this bacteria show different degrees of clinical signs represented by lethargy, recluse, loss of appetite, increase in respiratory rate and heart beat rate with different degrees of diarrhea appearing in a number of them. In others different forms of paralysis appear, either paralysis of the hind feet or complete immobility, in addition, to the occurrence of a number of deaths in mice infected experimentally with the infectious dose of bacteria. As for the results of the histological examination they are vaculation in the outer molecular layer, hyperplasia in the outer granular layer and part of it necrosis, loss of chromatin material for the nuclei of the cells of the polymorphic layer, detachment of the meningeal membranes, congestion of blood vessels as well as hemorrhage and inflammatory cellular infiltration and these symptoms are more severe in the half-lethal (LD-50) dose group. As for the groups treated with the two aforementioned antibiotics it is noted that they play an effective role in stopping diarrhea with mice somewhat regaining their activity, However they still had suffered from various tissue lesions represented by necrosis, vacuolation, degeneration, inflammatory cellular infiltration, congestion and hemorrhage.

Keywords

#