Neurosecretory Pathways in the Hypothalamo-Hypophyseal System

Abstract

Each scheme, in most cases, shows the hypothalamo-hypophyseal neurosecretory system of rats. Schemata 1-6 represent its frontal sections and schemata 7-12 its saggital sections. Schema 12 is a composite schema of schemata 7-11.In schemata 13 and 14 are compositely schematized the horizontal sections of the same system. Schema 13 shows the pathway of granules reaching from the nucl. paraventricularis to each part of the nucl. supraopticus and also to neurohypophysis, and schema 14 represents the pathway entering the neurohypophysis from each part of the nucl. supraopticus.(The pathways described in the present paper are partly omitted in schemata 13 and 14.) The explanation of abbreviations is put in the page facing figure-plate 1.Author's Abstract.With mature male mammals as test animals (rats, mice, rabbits and dogs) and by employing the aldehyde-fuchsin method, the substances produced by the hypothalamo-hypophyseal neurosecretory system are investigated and the superior staining affinities of the aldehyde-fuchsin method to the CHP method is confirmed.Pathway of neurosecretory granules are traced and an attempt is made to reveal the fiber connection, especially those between the neurosecretory nerve nuclei of the hypothalamus and the neurohypophysis.1. There are fibers (tractus paraventriculo-hypophyseus) reaching from the nucleus paraventricularis directly to the neurohypophysis. These fibers find their way to the dorsal side of the chiasma opticum or the tractus opticus, pass along in close proximity to each part of the nucleus supraopticus but independently of them and enter the median eminence from all its sides, especially from its rostral and lateral sides.2. There is no pathway of neurosecretory granules in certain fixed areas (A, A1, A2 and A3) around the 3rd ventricle.3. There are fibers reaching from the nucl. paraventricularis directly to each part of the nucl. supraopticus (the pars dorsolateralis, ventromedialis and tangentialis).4. Ther are fibers (tr. supraoptico hypophyseus) reaching from each part of the nucl. supraopticus directly to the neurohypophysis and there is a pathway of secretory granules leading from the pars dorsolateralis either to the pars ventromedialis or to the pars tangentialis. 5. Neither the tr. paraventriculo-hypophyseus nor the tr. supraoptico-hypophyseus is detectable in the form of a fiber bundle. The fibers are spread out expansively.6. In rats and mice, there is a pathway of neurosecretory granules leading from the pars dorsolateralis of the nucl. supraopticus to the pans ventromedialis or the pars tangentialis by way of the ventral side of the chiasma opticum and the origin of the tractus opticus.

Antidiuretic Activity in the Cerebrospinal Fluid

“…Moreover, Van Dyke, Bailey & Buey (1929) 3rd ventricle. Such light-microscopical studies on both mammals and sub-mammalian vertebrates have been published by Hild (1951), Bargmann (1954Bargmann ( , 1955, Stutinsky (1953), Okamoto (1957), Talanti & Kivalo (1961), Eichner (1963) and Dierickx (1964), and many of the authors suggest that the neurosecretory material is secreted into the CSF. These light-microscopical findings are supported by electron-microscopical investigations (Brightman & Palay, 1963;Smoller, 1965;Nishioka, Bern & Mewaldt, 1964;Leonhardt & Lindner, 1967).…”

Vasopressin and Central Integrative Processes

“…Anatomical evidence suggesting the secretion of neuro hypophysial peptides directly into CSF can be traced to light microscopical studies in both mammals and submam malian vertebrates [30,73]. Later electron microscopical ex amination supported these observations [10.…”