High-voltage electron microscopy of adrenal medulla: Direct connections between mitochondria and catecholamine-storage vesicles

Summary A high-voltage electron microscopic study of adrenal medullary cells from hypoglycemia-stressed rats revealed the existence of tubular channels which create a luminal continuity between the mitochondrial compartment and the catecholamine-storage vesicles. It is suggested that these channels allow for the transfer of materials such as high-energy nucleotides between the mitochondria and the catecholamine-storage vesicles without an intervening membrane.We thank Barbara Coalgate, Lin Cooper, Joann Cox, and the staff at the US Steel HVEM Laboratory for their assistance. This work was supported by NIH-DRR-70-4136, WVU Medical Corporation Research Grants, WVU Senate Research Grant, and West Virginia Heart Association Research Grant.