ELECTRON MICROSCOPIC OBSERVATIONS OF THE MESANGIOLYSIS THE TOXIC EFFECTS OF THE “HABU SNAKE” VENOM ON THE RENAL GLOMERULUS

Abstract

The cystic dilatation of the glomerular tuft due to the mesangiolysis was noted after the intravenous injection of the “Habu snake” venom (2mg per kg of body weight) into the rabbits. A total of 45 rabbits were used in this experiment and were sacrificed at selected intervals from a half to ten hours after the injections. The results obtained are as follows: 1. The initial change of the mesangiolysis is the decreased density of the mesangial matrix and successively small canaliculi formation in this area is noted. 2. The vacuolar swelling of the cytoplasmic processes of the mesangial cells is prominent. Some of them are seen beneath the endothelium, but others are pushing aside the endothelium and project into the capillary lumina. 3. In the next stage, the mesangial cells get to be in direct contact with the blood stream and their cytoplasm projects into the capillary lumina becoming flattened along the basement membrane. These findings would suggest the differentiation of the mesangial cells to the endothelium after the dissolution of the mesangial matrix by the venom. 4. Ultimately, the cystic dilatation of the glomerular tuft was observed. 5. In contrast to the easy dissolution of the mesangial matrix, the basement membrane shows only decreased density. This fact strongly suggests the qualitative difference between the two. 6. The findings of mesangiolysis and cystic dilatation in the glomerulus suggest that the glomerular tufts might be composed of sinus-like structure. The authors wish to express grateful appreciation to Prof. Dr. T. Kobayashi. They are also indebted to Assist. Prof. Dr. T. Okonogi (Gunma University, Japan). This study was subsidized by the Waksman Foundation of Japan.