Abstract
The magnocellular nuclei of the hypothalamus, the supraoptic nucleus and the paraventricular nucleus, are sites of formation of the so-called neurosecretory material in the diencephalon. Some information (Scharrer & Scharrer, 1954) is available on the question as to how early the formation of neurosecretory material commences in the cells of these nuclei: Dawson (1953) obtained by means of the aldehyde-fuchsin staining method, a positive reaction in the hypothalamus of the rat on the second postnatal day. In the dog, Scharrer (1954) observed, with chrome-hematoxylin, distinct granules in the hypothalamic nuclei about one week before birth. Benirschke & MacKay (1953) by the same method found a positive reaction in the human fetus as early as in the 20th week after the commencement of pregnancy. Moreover, some investigations with positive result have been made in this connection in the frog, Rana agilis, the chicken embryo and the cow embryo (Mazzi, 1954, Wingstrand
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
