BIBLIOGRAPHY. 567 



H. G. Beyer — Continued. 



physiological characters of which are sufficiently distinct to differentiate it from any other 

 known organism, and which, therefore, may be properly designated as Bacterium lactis. 



H. G. Beyer. The direct action of Atropine, Hyoscine, Hyoscyamine, and Daturine 

 on the Heart of the Dog, Terrapin, and Frog. 



American Journal of the Medical Sciences, April, 1887. 



The question of the action of atropine and its congeners on the vascular system of animals 

 has, perhaps, been the most difficult and perplexing which ever presented itself to the physi- 

 ologist. 



For a period Of fifty years physiologists have been engaged with this problem, many ex- 

 periments having been made, many bitter controversies having been fought out during this 

 time, and yet the question could hardly be said to have been satisfactorily answered. 



So far as the action of atropia on the heart is concerned, the best authorities still differ in. 

 about the following points: (1) That its action may be fully explained by assuming that a 

 paralyzing influence is exerted on the terminal filaments of the pneumogastrics ; (2) that 

 atropia at first stimulates and then paralyzes these filaments ; (3) that it not only paralyzes 

 these filaments, but also, and at the same time, stimulates the vaso-motor apparatus of the 

 heart. 



It seemed to me that the question of the action of atropine had gained anew in interest and 

 importance with the discoveries of Gaskell on the origin, course, and distribution of the nerves 

 supplying certain viscera. He found, for instance, that the heart of both cold and warm 

 blooded animals was supplied with two kinds of nerve-filaments, the stimulation of the one 

 accelerating and augmenting the heart's action, that of the other retarding or altogether stop- 

 ping its action. 



It was thought that by a careful study of the action of atropine on the isolated heart it 

 might be possible to attain good evidence as to how it affected at least the peripheral portions 

 of this double nerve-supply and whether it stimulates or paralyzes the one kind of nerves te 

 the exclusion of the other, or whether it affected both alike, and if so, how is this action influ- 

 enced by the quantity of the drug administered at the time ? 



After a great many experiments of this kind, the conclusions which were finally reached 

 were as follows : 



(1) Atropine, homatropine, hyoscine, hyoscyamine, and daturine are stimulants of the sym- 

 pathetic nerve-apparatus of the heart. 



(2) The vaso-motor portion of this nerve-apparatus is affected by comparatively small doses 

 of the drugs, giving rise to either acceleration or augmentation of the heart's action. 



(3) The inhibitory portion is excited by large doses only, giving rise to slowing of the heart's 

 action, and, finally, causing diastolic arrest. 



(4) The muscular substance of the heart is greatly excited by atropine, homatropine, and 

 daturine, and only slightly so by hyoscine and hyoscyamine. 



(5) The vaso-motor nerves and their ganglia are the first to become exhausted, the inhibitory 

 ganglia and their nerves are the next, and the muscular substance is exhausted last of all. 



(6) The slowing of the heart's action which follows the administration of these drugs in the 

 intact animal may be sufficiently accounted for by their influence on the inhibitory nerves 

 and ganglia of the heart itself. 



• (7) Tbe acceleration following the administration of certain doses of these drugs can not be 

 sufficiently accounted for by their action on the accelerator nerves and ganglia within the 

 heart, but is principally due to causes resident outside this organ. 



The essential points brought out by these experiments are that both vaso-motor as well as 

 inhibitory nerves are stimulated by the atropines, but that the former are affected by small 

 doses, the latter by large doses only ; hence a large dose causing an excitation of the vaso- 

 inhibitory portion of this nerve-apparatus may entirely cover up the vaso-motor excitement 

 which is present simultaneously with that of the vaso-inhibitory portion of the nerve-appa- 

 ratus. Inasmuch, however, as large doses quickly paralyze the vaso-motor apparatus, and 

 also as the vaso-motor become exhausted sooner than the vaso-inhibitory nerves, the slowing 

 of the heart's action following primary acceleration must be looked upon as a sign of much 

 greater danger than the latter, and is indicative of much more profound action, for if this influ- 

 ence is not arrested it will terminate in diastolic arrest. 



A point of interest needing to be emphasized is that different doses of the same drug may 

 produce results on the same organ that are diametrically opposed to each other. 



The influence of atropine on organs of similar innervation, as is the heart, is assumed to 

 be identical with that exerted on the heart. 



H. G. Beyer. On some of the problems to be solved by pharmaco-physiology, with 

 a new outline classification of Pharmacology. 

 Medical News, 1887. 

 In this paper some of the more important problems in pharmaco-physiology are discussed. 



