視床下部を中心とする形態学

Morphological Aspects of the Hypothalamus, especially on its Fiber-Connections

I．まえがき

　視床下部hypothalamusは前脳の内で発生学的には最も古い部分である。しかもその突起が下垂体の後葉になり，口腔の外胚葉からのびた突起とともに下垂体を作る。従つて最高の自律中枢である視床下部は発生学的に見ても下垂体と密接な関係にあることがわかる。

　脳髄の実験的研究はそれが生理学的，生化学的或は病理学的であつても，総てその形態学的知識がないと十分な研究結果を期待できない。そこで私は一般によく用いられる実験動物を中心にしてその視床下部の形態を周囲との連絡を重視しながら記述しようと思う。

The cytoarchitecture of the hypothalamus, including its fiber-connections with the sur-rounding areas is discussed.

From the results of our experimental and histological studies, the hypothalamus should be divided into three groups, namely, (1) the periventricular layer of the hypothalamus in connections with the periventricular layer of the preoptic area including its extension to the septum and with the subependymal layer of the central gray stratum by the so-called "A-group of fibers, " (2) the medial hypotha-lamic area in connections with the medial preoptic area and the inner layer of the cen-tral gray stratum by the so-called "B-group of fibers", and (3) the lateral hypothalamic area in connections with the lateral preoptic area, the septum, the outer layer of the central gray stratum and with the mesence-phalic tegmentum by the so-called "C-group of fibers".

Electrical stimulation of the groups (1) and (3), including their connected areas mention-ed above shows parasympathetic effects, while that of the group (2) including its connected areas mentioned above, shows sympathetic effects.