THE HISTOLOdY OF THE POISON-GLANDS OF BIFO AliUA 



AND ITS BEARING UPON THE FORMATION OF 



KIMNE1MIRIN WITHIN THE (iLANDS. 



BY P. G. SHIPLFA- AND <!. B. \\ ISI.OCKI. 



INTRODUCTION. 



During the autumn of 1910, considerable interest was aroused in the pharmacological 

 laboratories of the Johns Hopkins University by the milky secretion from the "parotid 

 glands" of the toads which were being used in an experimental study of the convulsant 

 action of certain organic dye-stuffs. Attention was first called to the peculiar character of 

 the secretion by the appearance of a bluish-green discoloration on knife-blades which had 

 come in contact with it; and the secretion being found to give the characteristic green color 

 of the pyrocatechin reaction when dilute solutions of it were treated with ferric chloride, 

 it was subjected to a thorough chemical and pharmacological study with the object of 

 ascertaining the composition of the poison. 



The results of this investigation were published by Abel and Macht (Abel and Macht, 

 1912) in the Journal of Pharmacology and Experimental Therapeutics, after a preliminary 

 report which appeared in the Journal of the American Medical Association (Abel and 

 Macht, 1911). They found that besides a highly volatile, odoriferous substance, which 

 they were unable to isolate, and a crystalline compound belonging, pharmacologically 

 speaking, to the digitalis group, which they called "bufagin," the crude venom contained 

 about 7 per cent of another crystalline body which on isolation and analysis was shown to 

 be dihydroxy-methyl-amino-ethylol-benzene (C 6 H 3 (OH) 2 CHOH. CH 2 NHCH 3 ) or epine- 

 phrin (adrenalin). 



That the epinephrin occurring in these glands is identical in every way with that sub- 

 stance as obtained from the suprarenal capsules was abundantly demonstrated by the polar- 

 metric, chemical, and physiological reactions of the crude venom and the pure crystalline 

 substance and (as will be shown later) the chromaffin reaction in microscopic secretions 

 serves to strengthen an identity already well established. 



These interesting findings naturally call for careful histological study of the poison 

 glands with special reference to the epinephrin content of the secretion. 



Several basic problems in connection with the venom and the structures in which 

 it is produced and stored at once suggest themselves for investigation. Is the epinephrin 

 produced in the poison-gland; and, if so, where and how? If the compound is formed 

 elsewhere than in the gland, what is the mechanism of its production and secretion? How 

 do the necessity for and the consequent synthesis by the organism of so great a quantity of 

 adrenalin affect the usual chromaffin organs adrenal, sympathetic system, etc.? Suppos- 

 ing epinephrin to be produced by the gland-cells themselves, what is the embryological 

 history of the gland and how does it happen that cells which originate from the epidermis 

 are capable of producing a substance supposedly characteristic of other and more highly 

 differentiated structures? 



This particular study was undertaken with the idea of establishing the presence of 

 chromaffin material in the venom and the gland parenchyma, to investigate histologically 



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