Autacoids of Posterior Lobe of Pituitary 99 



of the blood-vessels ; in this respect it differs from pars nervosa. Further, 

 extract of pars intermedia seems not to exhibit the specific effect on the 

 kidney and urine which are so marked with extracts of the whole posterior 

 lobe nor do repeat doses show any lessened effect, or prevent extracts of 

 pars nervosa from producing the usual results on blood-pressure, kidney, 

 uterus, and milk secretion. 



Herring has also found that extracts of the pituitary of the skate injected 

 into mammals, although they affect the uterus and mammary gland, have 

 no influence on blood- pressure or kidney. 



These observations appear to indicate that there are at least two specific 

 autacoids of the posterior lobe, both of which are present in the pars 

 nervosa of the ox and only one in the pars intermedia (and in the whole 

 pituitary of the skate). These autacoids are irrespective of that which 

 produces a fall of blood-pressure, the specific nature of which, although 

 probable, is less certain. 



