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THE PITUITARY GLAND: ANATOMY AND
HISTOPHY SIOLOGY
J. N . BALL AND BRIDGET I . BAKER
I. Introduction . . . . . . . . . . . . 1
A. The Pituitary Gland in General . . . . . . .
1
B. Adenohypophysial Histophysiology and Cytophysiology . .
2
11. The Pituitary Gland in Teleosts . . . . . . . . 4
A. General Organization . . . . . . . . . 4
B. Histophysiology of the Adenohypophysis . . . . . 9
C. The Neurohypophysis in Teleosts
. . . . . . 58
D. Blood Supply to the Teleostean Pituitary . . . . . 67
E. Hypothalamic Control of the Adenohypophysis . . . . 70
111. The Pituitary Gland in Primitive Bony Fishes . . . . . 74
A. Superorder Chondrostei . . . . . . . . . 74
B. Superorder Holostei
. . . . . . . . . 78
IV. The Pituitary Gland in Lungfishes . . . . . . . 81
V. The Pituitary Gland in Elasmobranchs . . . . . . 83
VI. The Pituitary Gland in Cyclostomes . . . . . . . 89
Acknowledgments
. . . . . . . . . . . 93
References . . . . . . . . . . . . . 93
I. INTRODUCTION
A. The Pituitary Gland in General
In all vertebrates, the pituitary gland or hypophysis consists of two
parts, separable on the bases of embryology, structure, and function.
These are the neurohypophysis, a downgrowth from the floor of the
diencephalon, and the adenohypophysis originating as an ectodermal upgrowth (Rathke’s pouch) from the roof of the embryonic buccal cavity
(Wingstrand, 1966a). The two parts meet and enclose between them a
mesodermal rudiment which gives rise to their intrinsic blood vessels
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