Failure to induce morphological changes in rats bone marrow following short-term administration of large doses of lead acetate

ABSTRACT

It is known that lead inhibits ferro-chelatase enzyme which catalyzes the transfer of iron from ferritin into erythrocytes protoporphyrins and thus causing the accumulation of the latter and iron containing granules in addition to morphological changes in bone marrow and circulating red blood cells [RBC]. Effectively, different lead-blood levels [pb-B] were produced by short-term daily administration [14 days] of 30 mg pb/kg b.w of rats through different routes [ig and ip]. The elevated pb-B caused mild decrease in hemoglobin level and related blood indices [P < 0.05] in rats intoxicated orally, while in ip, the decrease was more effective [P < 0.001]. Blood and bone marrow smears stained with Leishman's stain failed to show the characteristic iron staining granules or to produce morphological changes. This failure even in the presence of elevated pb-B was attributed to shorter duration of lead exposure