Selective Demonstration of the Golgi Structure and of Mitochondria

An easy and inexpensive method for demonstrating the classical Golgi structure or mitochondria is based on fixation in a mixture of barium nitrate, 5% aq., 1 part, and 10% neutral formalin, 4 parts. Fixation at 4–6° C. for 4–12 hours followed by a Cajal-type of silver impregnation and hydroquinone reduction demonstrates the Golgi structure. Fixation at room temperature for 24 hours followed by a chromating 2–3 days in 3%. potassium dichromate, washing in running water, dehydration and embedding prepares tissue for sectioning and staining with Heidenhain's iron-hematoxylin to demonstrate mitochondria. For the most successful impregnation of the Golgi structure in different tissues, it is necessary to vary the time of fixation, and a table of experimental data on optimum time is given. For most tissues, 8–9 hours give positive though not necessarily optimum results.