QUANTITATIVE HISTOCHEMISTRY OF RACHITIC RAT CARTILAGE ENZYME ACTIVITY DURING HEALING INDUCED BY VITAMIN D AND STARVATION

Abstract

Quantitative histochemical methods were used for assaying several dehydrogenases in various cell zones of the rachitic rat epiphyseal cartilage during healing brought about by either vitamin D administration or fasting for 48 hr. 6-Phosphogluconic dehydrogenase activity was significantly greater in the cells of both the proliferating and hypertrophic zones of rachitic control rats as compared to those from vitamin D-treated or fasted rats. Activity of 6-phosphogluconic dehydrogenase in the cells from proliferating and hypertrophic zones was identical in the different groups. Lactic dehydrogenase activity of proliferating and hypertrophic cells obtained from rachitic controls was markedly higher than those from the fasted animals. Minor differences were noted in the malic and isocitric dehydrogenases and peptidase in the cartilage cells obtained from vitamin D-treated, untreated and fasted rats.