[ harmful effect of quinolone [pefloxacine] on immature cartilage in juvenile rat]

The aim of our study was definition of the exact mechanism by which quinolone harm the immature cartilage causing arthropathy, and upon these results we can determine the suitable treatment for this damage. This effect was studied in four groups of juvenile wistar rats as following:1- normal group.2- the group of pefloxacine with a dose 15 mg/kg per day for one month. 3- the group of pefloxacine 15mg/kg per day for one month with addition of the magnesium ions with compensate amount 84mg/kg per art. 4- the group of pefloxacine 15mg/kg per day for one month with addition of vitamin E with compensate amount75mg/kg per rat. The drugs were administered by incubation tube for one months, and at the end of the experiment blood samples were took from animals hearts preparing for measuring malondialdehide, then animals were scarified and the maximum extension angle of the knee joints was measured, then we put the joints in the formol for the histological study. Pefloxacine increased the values of maximum extension angle significantly in compare to the normal group and the control group, with significant improvement in the group of magnesium ions and the group of vitamin E but non of each group could return the cartilage to the normal condition. The results of malondiadehyde assay inssure the effect of free radicals in this arthropathy. Histological study: pefloxacine damage significantly the cartilage and the damage was decreased in the addition of magnesium or vitamin E. There is a lot of factors participate in causing the arthropathy which induced by taking quinolone and this pathology don't confine on the participate of magnesium ions or oxidative stress.

[Studying the effect of the combination of angiotensin II receptor blockers [losartan] with glucocorticoids in the treatment of rheumatoid arthritis after inducing it in rats]

Rheumatoid arthritis is a chronic disease that lead to disability, and all drugs used to treat it have many side effects, the objective of this study is to investigate the effect of angiotensin receptor blockers [losartan], and their combination with glucocorticoids in the treatment of rheumatoid arthritis, after inducing this disease in rats. We studied this effect in male Wistar rats injected with complete freund's adjuvant [CFA] to induce this disease. And we investigated the effect of losartan, and its combination with dexamethasone in low dose, we compared too this effect with the effect of dexamethasone in low and high doses, the drugs were administrated On day 12[th] of the injection of CFA till the end of the experiment [day 28[th]], and at the end of the experiment, ankle joints from all groups were isolated for histological study. losartan reduced only the infiltration of inflammatory cells to the synovium, but it didn't reduce synovial hyperplasia and the destruction of the cartilage, but the combination of losartan with low dose of dexamethasone reduced all these parameters, and the efficacy of this combination was equal to the efficacy obtained by dexamethasone in high dose. The combination of losartan with low dose of glucocorticids leads to a significant efficacy in the treatment of rheumatoid arthritis, and so, with lower side effects of glucocorticoids.