THE PITUITARY BODY 



doses of posterior-lobe extract into mammals (e.g., from con- 

 trol concentrations of 13-2.0 mg. per cent to concentrations 

 of 30-40 mg. per cent). The change does not parallel that in 

 the blood-sugar concentration (Himwich and Fazikas, 1930; 

 Bischoff and others, 1931; Nitzescu and Munteanu, 1931; 

 Marenzi, 1934). CoUazo, Puyal, and Torres (1933) con- 

 cluded that moderate doses of extract cause a diminution in 

 the lactic acid of the blood and that only toxic doses cause an 

 increase. Certainly the doses used by other investigators 

 were large. 



If both glucose and posterior-lobe extract are continuously 

 injected intravenously into dogs, the hyperglycemia and 

 glycosuria are greater and the amount of glucose retained is 

 less than after the injection of glucose alone (Hines, Leese, 

 and Boyd, 19^7). The usual hyperglycemia after the injec- 

 tion of extract alone does not appear if the liver contains no 

 glycogen or if the liver has been excluded from the circula- 

 tion (Lambie, 1926; Imrie, 1929; and others). Depending 

 upon experimental conditions (dose, diet, period of starva- 

 tion, animal, etc.) the concentration of glycogen in the liver 

 may be diminished (Burn and Ling, 1929; Gomori and 

 Marsovszky, 1932; Gomori and Csomay, 1934) or remain 

 unchanged (Fukui, 1927; Bischoff and others, 1 93 1 ; Lawrence 

 and McCance, 1931; Murao, 1931) after single or repeated 

 injections of posterior-lobe extract.'^ 



The hypoglycemia which often follows posterior-lobe hy- 

 perglycemia usually is thought to be due to an increased 

 secretion of insulin (Blotner and Fitz, 1927; Velhagen, 1929; 

 Thaddea, 1933). From cross-circulation experiments in dogs 

 La Barre (1927-28, 1930) concluded that posterior-lobe ex- 

 tract causes a liberation of insulin by stimulating the pan- 

 creas directly. Epinephrin hyperglycemia may be reduced 

 considerably by the injection of posterior-lobe extract (Sten- 

 strom, 1913; Partos and Katz-Klein, 1921; Burn, 1923; 



'^ See also Nitzescu and Benetato (1931). 

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