EFFECTS OF EXTRACTS OF PARS NEURALIS 



striated muscle; the effects on the cutaneous vessels are con- 

 strictor whereas those on the vessels of the pia-arachnoid are, 

 perhaps, dilator (Clark, 1930; Forbes, Finley, and Nason, 

 1933). To cause vasoconstriction in isolated organs like the 

 ear or kidney of the rabbit, high concentrations of extract are 

 required; moreover, the effects on the same preparation are 

 not reproducible with any regularity (see Solntzew, 1928, and 

 Ssentjurin, 1928). Portman and Macdonald (1928) found 

 that even high concentrations of posterior-lobe extract were 

 without effect on the isolated carotid, femoral, or renal 

 arteries or veins. 



The effect of posterior-lobe extract on the formation of ly?nph 

 and edema fluid and on absorption. — The intravenous injec- 

 tion of a posterior-lobe extract into a dog from whose 

 thoracic duct the lymph is being collected is followed by 

 a prompt reduction in the flow of lymph. Chemical changes 

 in the lymph before and after injection have also been in- 

 vestigated (Meyer and Meyer-Bisch, 1921; Bayley and 

 others, 1922; Petersen and Hughes, 1925). The subcon- 

 junctival injection of a posterior-lobe extract into the rabbit 

 brings about a fall in the intra-ocular pressure which may 

 persist for several hours; the instillation of the extract into 

 the conjunctival sac is followed by scarcely any change 

 (Samojloff, 1927). Edema of the conjunctiva caused by 

 mustard oil, or by dionine, and inflammation of the skin 

 caused by mustard oil may be inhibited by the subcutaneous 

 injection of a posterior-lobe extract (Saxl and Donath, 1925; 

 Poulsson, 1927; and Tainter, 1928). Poulsson attributed the 

 inhibition or delay in chemosis to an effect on the capillaries. 

 He also reported that the subcutaneous injection of a pos- 

 terior-lobe extract prevented paraphenylenediamine-edema; 

 this report could not be confirmed by Tainter. Blalock and 

 others (1933) found that the intravenous injection of a 

 posterior-lobe extract into the dog did not prevent the loss 



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