Chapter III 



MICROSCOPIC ANATOMY 



The adrenals of many animal species have been studied 

 microscopically in great detail by numerous workers. Un- 

 fortunately much of the histological literature is conflicting 

 and unsatisfactory because of certain difficulties attendant 

 upon the study of the adrenals. These glands are noteworthy 

 for the rapidity with which they undergo autolytic change 

 after death. Moreover, the adrenals are extremely delicate 

 organs, and, as Hoerr 301 has pointed out, even the slightest 

 pressure will often cause artifacts to appear in the microscopic 

 sections. It is also difficult to fix the glands so as to avoid 

 the production of these artefacts. As a fixative, Hoerr recom- 

 mends Bensley-Helly's "Formol-Zenker," prepared by adding 

 nine volumes of an aqueous solution, containing 2.5 gs. of 

 potassium dichromate and 5.0 gs. of mercuric chloride per 100 

 cc, to one volume of neutralized formalin. In order to study 

 properly the morphological details of the cells Hoerr suggests 

 the use of several fixatives and different stains. Failure to 

 appreciate the difficulties inherent in obtaining good sections 

 has undoubtedly contributed to the confusion and misinter- 

 pretations which abound in the anatomical literature. Many 

 of the morphological descriptions of bizarre cell structures are 

 mere artifacts to which no physiological significance is to be 

 ascribed. It is particularly difficult to obtain specimens of 

 human adrenals soon enough after death to avoid post-mortem 

 changes. 



The adrenals of some species undergo radical changes dur- 

 ing certain periods of life. The most striking of these changes 

 involves the development and involution of the androgenic 

 zone to be described in the next chapter. Failure to appre- 



37 



