SISTER-CHROMATID EXCHANGE FREQUENCY IS ELEVATED AND CELL-PROLIFERATION IS DELAYED IN BONE-MARROW CELLS OF STARVED AND MARGINALLY MALNOURISHED RATS

The frequency of sister chromatid exchanges (SCE) and the cell prolife ration kinetic were analyzed in bone marrow (BM) cells of Wistar rats subjected to starvation and marginal malnutrition (MN) after 24h of 5- bromodeoxyuridine (BdUr) implantation. SCE were analyzed in a minimum of 18 consecutive second division metaphases and for cell proliferatio n, 100 consecutive metaphases were analyzed and classified into the fi rst, second and third or subsequent replication cycles. Rats subjected to starvation and MN exhibited significantly higher mean SCE per lymp hocyte in bone marrow than the well nourished rats. Further, they also showed a longer proliferation kinetic in BM cells. These observations indicate that starvation and MN per se resulted in greater SCE and pr olongation of the cell cycle in experimental animals. On rehabilitatio n, the cells with high SCE frequency and prolonged cell cycle in both starved and MN rats were comparable to control groups.