Influence of Bacterial Endotoxins on Bone Marrow and Blood Components

Endotoxin (Lipopolysaccharide, LPS) a component of the bacterial wall of gram-negative bacteria, has been recognized as one of the most potent bacterial products in the induction of host inflammatory responses and tissue injury and was used in this study to mimic infections. LPS induces production and release of several cytokines. In response to these cytokines, different effects of endotoxins are seen.
The effect of three types of endotoxins (Escherichia coli, Klebsiella pneumoriae and Salmonella typhimurium) on bone marrow, differential counts and peripherial blood parameters were investigated in adult rats.
Male spraguo Dawely albino rats weighing 220 - 250 g were used. They were injected i.p. (1 mg/kg body weight) with single dose of 3 types of endotoxins. Blood samples were collected from the experimental animals at 24 and 72 hours of the injection. At 72 hours the bone marrow aspirations were harvested from the femur of the rats for microscopic examination.
Endotoxins induced different changes in the cells of bone marrow. Also, lipopolysaccharide caused significant decreases in red blood cells, white blood cells and platelets counts, hemoglobin content and hematocrit percent.
Data of the present study point out to the dose of these toxins according to suitable pharmacopeia. Lemulus amebocyte lysate (LAL) test is specificly used for determination of the endotoxin limit. This recommendation should be observed to avoid the toxic effects of endotoxins.