164 



Scientific Proceedings (39). 



105 (515) 



Studies on experimental arterial lesions in the dog. 



By ISAAC LEVIN and JOHN H. LARKIN. 



[From the Department of Pathology, College of Physicians and 

 Surgeons, Columbia University^ 



While it is easy to produce experimentally an arterial lesion in 

 the rabbit, it is extremely difficult to repeat the same in the dog. 

 All attempts to produce arterial lesions in normal dogs, by injec- 

 tion of adrenalin or other similar substances, failed. Carrel and 

 Guthrie, Stich and others stated that the walls of a segment of a 

 vein implanted in an artery undergo certain changes which consist 

 in a hyperplasia of the connective tissue of interstitia, and in an 

 increase of the number of the muscular and elastic fibers of the 

 media. But it is hardly possible to draw a correct conclusion 

 from this method of experimentation, since such a segment is 

 completely severed from its vascular and nerve connections. 



Since the majority of writers on arteriosclerosis maintain that 

 the mechanical increase of blood pressure is the most important 

 factor in the causation of the disease, we endeavored in our experi- 

 ments to increase the blood pressure within the lumen of a vein 

 by the following method: 



An anastomosis was performed between the central end of a 

 carotid and the peripheral end of the external jugular vein, thus 

 not only reserving the venous circulation within the blood vessel, 

 but also adding to it the pressure of the arterial blood flowing 

 from the artery. 



A certain number of dogs received also from three to five intra- 

 venous injections of adrenalin, in order to investigate whether the 

 drug would have any effect on a vein which was already placed 

 under unfavorable conditions of pressure. As a result of the 

 operation there took place in a certain number of cases a dilatation 

 of the external jugular and its branches, with a slight thickening 

 of the vessel wall. In other dogs there took place dilatation of 

 the vein for a distance of about half an inch, where the walls of 

 the blood vessel seemed to arrest the dilatation. Microscopically 

 there was neither degeneration nor hyperplasia of the intima or 



