Histological and Chemical Changes in the Rat Pituitary Neural Lobe following Treatment with Neurohypophysial Substances

Abstract

No agreement exists as to the effect of administration of exogenous posterior pituitary principles on neurohypophysial structures. Some authors¹ describe no changes in neurosecretory phenomena, others² think the dosage important, whereas increase in neurosecretion has been reported by me³. One of the difficulties in evaluating and comparing alterations in material stained with chrome-alum hæmatoxylin is the lack of adequate histological assaying methods. When the amount of chrome-alum hæmatoxylin-positive material has not increased considerably following hormone treatment, it is difficult to be reasonably certain of the effect. In addition, not all such material necessarily represents posterior pituitary hormone or ‘true’ neurosecretory material^3,4.