Morphological study of the pituitary gland of the studanese Nile fish Clarias Lazera

الملخص EN

The histology of the pituitary gland of C.

lazera was studied using some standard techniques employed in the study of vertebrate pituitary.

The pituitary gland is attached to the infundibular region of the brain by a cylindrical infundilbular stalk.

The gland is composed of two main divisions; the pars glandularis and the pars nervosa.

The former is subdivided into an anterior, middle and posterior glandular regions.

The anterior glandular region is composed mostly of clusters of acidophils which surround blood capillaries, giving the region a follicular appearance.

The middle region is composed of basophils, acidophils and chromophobes.

The distribution of the three types of cells has no definite pattern.

The basophils are characterized by possessing colloidal globules, and therefore such basophils are described as globular basophils.

The posterior region is formed mostly of dull acidophils, with few interspersed dull faint basophils.

The two types of cells are scattered singly or in groups arround the branches of the pars nervosa.

The pars nervosa, which is the continuation of the infundibular stalk, form a central core around which the three glandular regions of the pituitary gland are arranged.

The processes of the pars nervosa are elaborate, with a fanning root – like nature, in the posterior glandular region and scanty in both the anterior and middle glandular regions.

The pars nervosa appears as a fibrous tissue with scattered nuclei belonging to neuroglia cells.

It is characterized by the colloidal Herring materials, basophil and acidophilic glandular cells.

Infundilbular stalk, which link the floor of hypothalamus and the terminal zone of the anterior glandular region was found to be a thin lamina of nervious tissue with a layer of epindymal cell lining the third ventricle.

The middle glandular region was found to consist of three chromophils cells, only one type of acidophil was identified.

It took both OG and erythrosin.

The other two types were found to be basophilic and they were designated as type 2 and type 3.

Basophils type 3 were PAS, AF positive but AB negative.

The pars nervosa was found to be small, and contained more stainable neuro-secretory materials.