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The Relation of the Islets of Langerhans to the Pancreatic Acini 

 under Various Conditions of Secretory Activity. 

 By John Ho mans, M.D. Boston. 



(Communicated by Prof. E. H. Starling, F.E.S. Eeceived October 1, 1912, — 



Bead January 23, 1913.) 



(From the Institute of Physiology, University College, London.) 

 [Plates 2 and 3.] 



The object of this research* was to examine the relations of the islets of 

 Langerhans to the pancreatic acini under the following conditions : first, at a 

 time when the pancreatic tissue had been cut down to a very small amount, 

 and second, when the gland had been exhausted by the action of secretin. 



Under the first of these conditions it was expected that, as the removal of 

 the entire pancreas was inconsistent with life, the removal of all but a little 

 might lead to the hypertrophy of one or both elements in the part remaining, 

 and throw some light on the possibility of a change of acinous to islet tissue 

 or the reverse. As a control to this procedure the pancreatic ducts were 

 ligatured in one animal because the pancreatic acini rather than the islets are 

 generally supposed to degenerate under these circumstances. In the second 

 series of experiments — exhaustion of the gland by secretin — it was intended 

 to test the assumption by Dale, Vincent and Thompson, and others, that this 

 proceeding induces a change of acinous into islet tissue. 



It is hardly necessary for me to summarise the literature of this subject 

 beyond repeating the most typical of the opposing views as to the functional 

 and anatomical independence of the islets and their relation to acinous tissue. 

 Banged on the side that the islets are more or less interchangeable with acini 

 are a number of investigators, whose views, however, show important 

 differences of detail. Lewaschew (1886) holds that as a result of exhaustion 

 acinous cells become converted into islet tissue and are capable of re-forming 

 after rest. Laguesse (1893-1911) maintains a somewhat similar view of 

 " balancement " between the tissues, both on embryologic grounds and as a 

 result of a long series of anatomical and experimental observations. He 

 considers, however, that the islets have an independent function. Mankowski 

 (1902) considers that the islet is the highest stage of acinous cell activity 

 into which all such cells must go. Dale (1904) sees, as a result of exhaustion, 



* The research was carried out with the aid of funds from the Peter Bent Brigham 

 Hospital of Boston, U.S.A. 



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