AtJTHOR S ABSTRACT OP THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE, SEPTEMBER 26 



STUDIES IN THE DYNAMICS OF HISTOGENESIS. 

 TENSION OF DIFFERENTIAL GROWTH AS A 

 STIMULUS TO MYOGENESISi 



VII. THE EXPERIMENTAL TRANSFORMATION OF THE SMOOTH 



BLADDER MUSCLE OF THE DOG, HISTOLOGICALLY INTO 



CROSS-STRIATED MUSCLE AND PHYSIOLOGICALLY 



INTO AN ORGAN MANIFESTING RHYTHMIC A LITY 



EBEN J. CAREY 



Department of Anatoviy, Marquette University Medical School, Milwaukee^ 



Wisconsin 



TWENTY FIGURES 



INTRODUCTION 



It has been the problem of the writer for a number of years to 

 determine experimentally whether an undifferentiated mesen- 

 chymal cell subjected to an optimum tension would develop into 

 a muscle cell. The technical details of this problem have not yet 

 been surmounted. If, however, the various types of muscle 

 cells found in the body, viz., smooth, cardiac, and skeletal, 

 represent resultants of different degrees of optimum tension 

 (Carey, '19-20 a; '20 b), then the proof for this idea would be 

 forthcoming if non-striated muscle could be converted into cross- 

 striated muscle by varying the velocity of application and the 

 intensity of the tensional stimulus to a higher optimum degree. 



It is held at the present time that the essential difference 

 between the types of developed muscle is the presence or absence 

 of cross-striations. From the purely static and structural stand- 

 point, these cross-bars are the outstanding feature. On the 

 other hand, from the dynamic or functional and embryological 



1 This thesis was granted first prize in the competition for the medical prize 

 scholarship for original research by the medical faculty of the University of 

 Chicago, Rush Medical College, 1921. 



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THE AMERICAN JOURNAL OF ANATOMY, VOL. 29, NO. 3 



