Grandi D, Arcari M L, Azzali G
Istituto di Anatomia Umana Normale dell'Università degli Studi di Parma.
Acta Biomed Ateneo Parmense. 1993;64(3-4):51-80.
The Pituitary of the Alosa fallax nilotica consists of a pars distalis, a pars intermedia and a pars nervosa. The pars distalis is divided into rostral and proximal. The pars nervosa extends also into proximal pars distalis. The rostral pars distalis, on the contrary in primitive Teleostei, has organized into cellular cords defining cavities or intercommunicating follicles. These latter finish into the oral adenohypophysial duct, which don't open in pharyngeal cavity. The cords contain three cell types: the columnar cells LTH, TSH cells and basal cells not yet functionally determined. The cord cells are separated from follicle cavity by an one layer of flat degranulated cells. The LTH cell, the chief cell type, together the TSH and basal cells shows evident cytologic differences in organelles of synthesis and secretion during the various stages of the reproductive migration. Besides globular and baton-shape projections are underlined in the apical cytoplasm of LTH cells. These structure, extending into follicle cavity, seem to dispatch sensory function probably. The proximal pars distalis consists of compact cords of gonadotropic cells (particularly active during the stage of migration from rivers to the sea) with inserted orangiophilic cells (probably STH) and phloxine cells: these latter cells are chiefly arranged at the periphery and immunocytochemical positive for the antibodies against ACTH. The pars intermedia contains cord of ACTH cells, particularly manifest during the periods of transit from sea water to fresh water and on the contrary, they are characterized by positive-ACTH dense granules. On the ground of ultrastructural aspects of vesicles, the pars nervosa shows three types of nervous fibers which correlate with neurosecretory hypothalamus and catecholaminergic dopaminergic fibers. The Authors think of underlining particularly that the all cells of rostral pars distalis and chiefly the LTH cells are involved significantly in the regulation of reproduction and hydro-mineral metabolic equilibrium.
尼罗河鲱的脑垂体由远侧部、中间部和神经部组成。远侧部又分为吻部和近端部分。神经部也延伸至远侧部的近端部分。与原始硬骨鱼相反，吻部远侧部已组织成细胞索，形成腔隙或相互连通的滤泡。这些滤泡最终汇入口腔腺垂体管，该管不开口于咽腔。细胞索包含三种细胞类型：柱状促乳素细胞、促甲状腺激素细胞和功能尚未确定的基底细胞。索状细胞与滤泡腔之间由一层扁平的脱颗粒细胞分隔。促乳素细胞是主要的细胞类型，与促甲状腺激素细胞和基底细胞一起，在生殖洄游的各个阶段，合成和分泌细胞器表现出明显的细胞学差异。此外，促乳素细胞顶端细胞质中有球状和棒状突起。这些结构延伸至滤泡腔，似乎可能具有感觉功能。近端远侧部由促性腺细胞紧密的细胞索组成（在从河流洄游至海洋的阶段特别活跃），其中夹杂着嗜橙色细胞（可能是生长激素细胞）和焰红染细胞：后一种细胞主要排列在周边，对促肾上腺皮质激素抗体免疫细胞化学呈阳性。中间部含有促肾上腺皮质激素细胞索，在从海水过渡到淡水的时期尤为明显，相反，它们的特征是促肾上腺皮质激素密集颗粒呈阳性。从囊泡的超微结构来看，神经部显示出三种类型的神经纤维，它们与神经分泌下丘脑和儿茶酚胺能多巴胺能纤维相关。作者特别强调，吻部远侧部的所有细胞，尤其是促乳素细胞，在生殖调节和水盐代谢平衡中发挥着重要作用。
