ABSTRACT
In order to evaluate the potential effect of Nigella sativa seed's oil [NSO] on experimentally induced diabetes, alloxan was injected intra- muscularly in a single dose of 175 mg/kg in adult male albino rats. A group of animals was kept diabetic for fifteen days, another group for three months and a third group was injected with alloxan then after four days were treated daily with NSO for fifteen days. A fourth group was treated with NSO after three months of alloxan injection. The fifth group was kept as control. Alloxan caused degranulation and massive destruction of beta cells, especially after three months of diabetes induction. Treatment of early stage of diabetes [after four days of alloxan injection] with NSO prevented the subsequent changes by alloxan. NSO had no role in the treatment of chronic diabetes [at late stage]. As regard these findings, the anti-diabetic effect of NSO was clearly observed only in the treatment of early stage of diabetes rather than after three months of the diseases. It was concluded that the anti- diabetic effect of NSO may be through its protective effect on beta cells, especially in early stage of the disease