Effect of dimethoate on the immune system of female mice.

The functional status of the immune system of female mice exposed to a single oral dose of dimethoate (16 mg/kg) was evaluated by assessing cell mediated and humoral immune responses, in addition to the effect of dimethoate on spleen and body weights after different time intervals. The data showed that dimethoate caused a time-depended decrease in spleen weights in the absence of a change in body weights. The immunologic effect of dimethoate to female mice produced a dose-dependent decrease in the number of the rosette forming cells (total and active erythrocyte rosette). The ability of splenocytes to proliferation in response to mitogens; phytohemagglutinin (PHA) for T cell and lipopolysaccharide (LPS) for B cell were significantly decreased at the different times. As compared to control, a significant decrease in serum total immunoglobulins (Ig) and IgM was found, while IgG was non-significant deceased. Results of this study also revealed that dimethoate caused a significant decrease in the number of plaque forming cell (PFC/10(6) splenocytes) in a time dependent manner.