ENZYMATIC-PROPERTIES OF TRANSPLANTED GLOMERULOSA CELLS

There are several theories about the physiologic regeneration of adren als and maintenance of physiologic steroid secretion after subtotal lo ss of adrenal cortical cells. According to the cell migration theory, adrenocytes from the zona glomerulosa migrate centripetally toward the medulla. This theory is opposed by the zonal theory according to whic h each zone resplenishes its cells independently. What these theories have in common is that they are based on data from the intact adrenal gland. We transplanted purified glomerulosa cells under the kidney's c apsule of Lewis rats. The tissue was removed 30, 60, 90, and 150 days after transplantation to investigate the presence of two specific enzy mes that are responsible for the secretion of aldosterone and corticos terone. Cytochrome p-450as is specific for glomerulosa cells producing aldosterone, and cytochrome p-45011 beta is specific for fasciculata cells producing corticosterone. After sequencing the genetic code of t hese enzymes it became possible to demonstrate expression of the enzym es by in situ hybridization. The transplanted glomerulosa cells turned their enzymatic property to fasciculata cells expressing cytochrome p -45011 beta. Our results suggest that glomerulosa cells are able to ta ke over the physiologic function of a whole adrenal cortex in the abse nce of fasciculata cells, and that they are sufficient to maintain the function of the adrenal cortex.