EFFECTS OF EXTRACTS OF PARS NEURALIS 



Fujino, 1931; and Silver and Mislowitzer, i93i)/9 Blotner 

 and Fitz suggested that this perhaps is due to insuHn hbera- 

 tion. 



Ergotamine does not prevent posterior-lobe hyperglycemia 

 but may prevent epinephrin hyperglycemia (Clark, 1926; 

 Nitzescu, 1928; Thaddea, 1933).'" Although it is stated in 

 some reports that the adrenal glands reinforce or are neces- 

 sary for the production of posterior-lobe hyperglycemia 

 (Fritz, 1928; Yamamoto, 1929; La Barre, 1930; Houssay and 

 Di Benedetto, 1933), this seems unlikely and is denied by 

 Clark (1926) and Thaddea and Waly (1933). 



The effects of extracts of the pars neuralis on the metabolism 

 of fats. — Coope and Chamberlain (1925) reported that the 

 subcutaneous injection of a large dose of posterior-lobe ex- 

 tract into rabbits or rats was followed in 10-15 hours by an 

 increase in the concentration of fat (determined as fatty 

 acids) in the liver. Histologically the change was found to be 

 a fatty infiltration. Coope (1925) later reported that the 

 change could be prevented by the injection of insulin (40 

 units of insulin antagonized the effects of 4 cc. of posterior- 

 lobe extract in the rabbit). This increase in the concentra- 

 tion of liver-fat due to the injection of posterior-lobe extract 

 often is neither as striking nor as easily elicited as the first 

 results of Coope and Chamberlain suggested. The finding 

 was not confirmed in the small group of experiments of van 

 Dyke (1926). Oshima (1929) confirmed the observations of 

 Coope and Chamberlain; he found that the injection of oes- 

 trone or thyroxin into rabbits causes a similar but perhaps less 

 pronounced change. In the experiments of Hynd and Rotter 

 (1932) rats were used. Many of their results were irregular. 



" Under different conditions (intravenous injection) posterior-lobe extract with 

 epinephrin may cause a greater hyperglycemia than that following epinephrin alone 

 (Houssay and Di Benedetto, 1933). 



^° Posterior-lobe hyperglycemia is prevented in the cat and in man by the ad- 

 ministration of ethyl alcohol (blood concentration of alcohol greater than 100 mg. 

 per cent) (Murray, 1933). Is this due to an effect of alcohol on the liver? 



[363] 



