Histological Studies on the Hypothalamic Neurosecretory Nucleus. V. Phase Contrast Microscopic Observations on the Hypothalamic Neurosecretory Cell of Dog. (Contributions to the Comparative Histology of the Hypothalamohypophysial System. 32nd report.)

Abstract

The fixed or non-fixed hypothalamic neurosecretory cells of the dog in the normal condition were observed by the phase contrast method, and, further, their findings were compared with those observed with the section stained by GOMORI's method. The results obtained run as follows: 1. For the mounting, in point of the propriety of contrast and distinctness of figures, a 40% sucrose solution is the best for non-fixed sections, while, for fixed sections, an original solution of glycerin is the most suitable medium. 2. In case of fresh hypothalamic neurosecretory cells, many fine spherical granules appearing dark by Positive-Medium are observed in the cytoplasm other than NISSL area and in the processes. 3. These granules are identified with the neurosecretory granules for the result of their comparison with the granules observed in the section stained by GOMORI's method, and by the reason that no like granules have been found in the PURKINJE's cell of cerebellar cortex as well as in the pyramidal cell of cerebral cortex observed as controls. 4. Mitochondria are observed as short-bacillar granules, brighter than, and yet discriminated from, neurosecretory granules. 5. NISSL's substance is observed as optically homogeneous, darkish, large granules or rough, large masses in the peripheral cytoplasm where few neurosecretory granules and few mitochondria are found, and its findings are in accord with those observed in the section fixed and stained after NISSL's method. 6. The above-mentioned findings are obtained in the paraffin section fixed with ZENKER's fluid, BOUIN's fluid and formalin, too. In these cases, however, their distinctness is inferior to the one in the non-fixed section. 7. In the paraffin section of hypothalamic neurosecretory nucleus fixed with alcohol, neurosecretory granules are not observed in the cytoplasm of a neurosecretory cell even by the phase contrast method. 8. GOLGI apparatus or so-called GOLGI body cannot be confirmed in the hypothalamic neurosecretory cells, fresh as well as fixed with ZENKER's fluid etc., yet when these cells are fixed after AOYAMA's method, even without silver impregnation, meandering, sometimes anastomotic canalicular structures that might be considered GOLGI apparatus, are observed just as in the silver impregnated preparation. © 1957, International Society of Histology and Cytology. All rights reserved.