Influence of the Pituitary Anterior Lobe Upon the Specific Dynamic Action of Protein

Abstract

The results obtained in the numerous experiments dealing with the influence of hormones on the specific dynamic action of protein are extremely contradictory ; even the simple question as to how the specific dynamic action of protein is influenced by pathological states of hypo\ x=eow-\ and hyper-thyroidism has not been answered satisfactorily [Serejski & Jisslin, 1930]. Abelin [1923] reports an increase in the specific dynamic action of protein after administration of thyroid extracts, while Feuling [1933] and Schittenhelm & Eisler [1932] observe a decrease after administration of thyrotrophic hormones. The reports on the specific dynamic action in hypophyseal pathology are especially conflicting. Plaut [1922 a, b], Liebesny [1925], Kestner, Liebesch\l=u"\tz-Plaut & Schadow [1926] and Peters [1930] found a decreased specific dynamic action of protein in pituitary hypofunction. Fulton & Cushing [1932] and Johnston [1932] were, however, unable to observe any change in patients with disturbed hypophyseal function. Gaebler [1929] found the specific dynamic action of protein unchanged in a hypophysectomized dog. According to Foster & Smith [1926] the specific dynamic action of glycocol is decreased in hypo¬ physectomized rats, though Evans, Luck, Pencharz & Stover [1938] found it unchanged.The present experiments were carried out in order to study systematically the specific dynamic action of protein in rats at certain times after hypophysectomy and also the influence of some of the well-known hormones of the pituitary anterior lobe on the specific dynamic action. MethodsThe animals used were adult Wistar rats, weighing 120-180 g. Hypo¬ physectomy was performed by the paratracheal route and only those experiments were considered where removal of the hypophysis could be regarded as complete.The animals were not given any food for 10-14 hours before the experi¬ ments were started. The basal metabolism of these fasting animals was determined for two or three normal periods, then fresh egg albumen was administered. This was given orally by means of a Record syringe with an