While a 60 mg/kg i.p. dose of STZ induced type 2 diabetes in the rat and suppressed the insulin output by about 82% of the control value (p<0.001), a pretreatment with any of the test compounds was able to preserve the ability of pancreas to secrete insulin following a treatment with STZ (Figure 4B). This evidence concerns the gene INS and type 2 diabetes mellitus.