The growth and metastasis of four commonly used tumour lines implanted into eight different sites: evidence for site and tumour effects.

The growth and metastasis of four commonly used experimental tumour lines have been compared after the implantation of cells into a lobe of the liver, the spleen, the left kidney, the peritoneal cavity, the thorax, the right thigh muscle, subcutaneously into the dorsolumbar region and intravenously into the tail vein or the right femoral vein. This was done to assess the importance of site in affecting metastatic distribution, and to determine whether any general conclusions could be drawn as to the role of this factor. Tumours grew at variable rates in different sites, but this did not affect the extent or distribution of metastasis. Each line gave a characteristic pattern that could be considerably modified by site. For example, in the spleen, metastasis was always extensively to the liver; in the kidney, and to some extent in the muscle, metastasis was similar to that obtained for intravenously injected cells; in the peritoneal cavity or thorax, metastasis was usually lower than from other sites; and in the liver, the metastasis to other lobes of the liver and to the lungs was modified. Many of these findings could be explained by both specific and non-specific factors operating at each site. It is suggested that interactions at the primary site of tumour growth may be very important in affecting metastasis, and that in the future more attention should be given to this factor in order to make progress in understanding tumour spread.

Studies on glomerular basement membrane in experimental diabetes using lectin histochemistry in Wistar rats.

This study was designed to establish whether specific early changes in carbohydrate content of proteins in the glomerulus of the diabetic rat could be detected. Lectin staining of kidney sections from streptozotocin-induced diabetic rats were compared with similar sections from healthy and diabetic rats that were treated with insulin. Animal groups were killed 1 month, 3 months and 6 months after induction of diabetes. There were no differences in the staining of the glomerular basement membrane between control, insulin-treated and diabetic rats for the lectins concanavalin A, lotus tetragonolobus, soybean and kidney bean, with and without trypsinisation. Staining of the glomerular basement membrane with wheat germ agglutinin after trypsinisation was significantly increased in the diabetic group when compared to both healthy and insulin-treated groups (p less than 0.01). It was concluded that, in experimental diabetes mellitus in the rat, there is an accumulation of substances in the glomerular basement membrane and mesangium with an affinity for wheat germ agglutinin, most probably N-acetyl glucosamine, and this is partially prevented by insulin treatment.