Analysis Of Electrical Activity In The Blood Vessel Wall In Experimental Atherosclerosis

ANALYSIS VESSEL

OF WALL

ELECTRICAL

ACTIVITY

IN EXPERIMENTAL

IN T H E

BLOOD

ATHEROSCLEROSIS UDC 616.13-004.6-092.9-073.97

A. K. Chepurov

E l e c t r i c a l activity of the walls of intact blood v e s s e l s and the blood v e s s e l s of r a b b i t s kept on an atherogenic diet was investigated in a t r a n s p a r e n t plastic c h a m b e r containing a e r a t e d K r e b s ' solution. With the development of a t h e r o s c l e r o t i c changes in the v e s s e l wall, the potential difference between its intima and adventitia is reduced. The m o s t m a r k e d m o r p h ological and e l e c t r i c a l changes in the v e s s e l wall in a t h e r o s c l e r o s i s a r e o b s e r v e d in the a b dominal a o r t a and f e m o r a l a r t e r y .

Clinical and e x p e r i m e n t a l investigations have shown that a t h e r o s c l e r o s i s is m a n i f e s t e d p r i n c i p a l l y by m o r p h o l o g i c a l and functional changes in the blood v e s s e l wall [1, 2, 5, 7, 8, 11, 16]. The coagulant a c tivity of the v e s s e l wall is i n c r e a s e d and its anticoagulant and fibrolytie activity is reduced [6, 12, 14, 15]. It is c o n s i d e r e d that changes in the coagulant p r o p e r t i e s of the v e s s e l wall and d i s t u r b a n c e of its m o r p h ological integrity a r e i m p o r t a n t f a c t o r s in the pathogenesis of i n t r a v a s e u l a r t h r o m b o s i s in a t h e r o s c l e r o s i s [6, 10, 15]. Most w o r k e r s s t a t e that functional changes in the v e s s e l wall in a t h e r o s c l e r o s i s a r e a s s o c i a t e d with m e t a b o l i c d i s t u r b a n c e s taking place in it [11, 16]. Recent work has shown that active ion t r a n s p o r t t a k e s place through the v e s s e l wall, and is d e t e r m i n e d by the c h a r a c t e r of its e l e c t r i c a l activity and the magnitude of the z e t a - p o t e n t i a l of the boundary l a y e r of moving blood [3, 4, 9, 16]. It can t h e r e f o r e be postulated that a t h e r o s c l e r o s i s is a c c o m p a n i e d by changes in the e l e c t r o c h e m i c a l c h a r a c t e r i s t i c s of the v e s s e l wall. The object of the p r e s e n t investigation was to study the e l e c t r i c a l activity of the intact v a s c u l a r wall and its changes in the wall of blood v e s s e l s of r a b b i t s with e x p e r i m e n t a l a t h e r o s e l e r o s i s . EXPERIMENTAL

METHOD

E x p e r i m e n t s w e r e c a r r i e d out on 17 r a b b i t s weighing 2.5-3 kg. Group 1 consisted of control a n i m a l s (9 rabbits), group 2 of animals r e c e i v i n g c h o l e s t e r o l in a dose of 0.5 g / k g body weight daily with the diet for 8 months (8 r a b b i t s ) . The m o s t m a r k e d changes in a t h e r o s c l e r o s i s a r e o b s e r v e d in the f e m o r a l v e s s e l s , at the bifurcation of the a o r t a , and in the abdominal a o r t a . Accordingly, e l e c t r i c a l activity was studied in the abdominal p a r t s of the a o r t a and i n f e r i o r vena cava, and also in the f e m o r a l a r t e r y and vein. F o r this p u r p o s e , the blood v e s s e l to be investigated was excised under intravenous u r e t h a n e a n e s t h e s i a (10 m l of a 20% solution) and all the p e r i v a s c u l a r t i s s u e s c a r e f u l l y r e m o v e d . The d i s s e c t e d p a r t of the blood v e s s e l , 4-5 cm long, was incised longitudinally. The a p p a r a t u s used to study e l e c t r i c a l activity of the v e s s e l wall in vitro is s h o w n d i a g r a m m a t i c a l l y in Fig. 1. The segment of blood v e s s e l f o r testing was placed between two halves of a t r a n s p a r e n t p l a s t i c c h a m b e r , joined t o g e t h e r h e r m e t i c a l l y by m e a n s of s c r e w s . The two halves of the c h a m b e r w e r e filled with K r e b s ' solution of the following composition (in g / l i t e r ) : NaCl 7.7; NaHCO 3 1.36; NaH2FO 4 0.165; KC1 0.347; CaC12.6H20 0.272; MgC12.6H20 0.01; glucose 1.4. The K r e b s ' solution was t i t r a t e d to pH 7.4. A g a r bridge e l e c t r o d e s , p r e p a r e d in the usual way, w e r e placed 2 m m away f r o m the s u r f a c e of the intima and adventitia of the blood v e s s e l . The o t h e r ends of the a g a r b r i d g e e l e c R e s e a r c h Institute of Age Physiology, A c a d e m y of Pedagogic Sciences of the USSR, Moscow. ( P r e sented by A c a d e m i c i a n V. V. Parin.) T r a n s l a t e d f r o m Byulleten' ~ k s p e r i m e n t a l ' n o i Biologii i Meditsiny, Vol. 71, No. 5, pp. 31-34, May, 1971. Original a r t i c l e submitted June 25, 1970.

9 1971 Consultants Bureau,. a division of Plenum Publishing Corporation, 227 West i7th Street, New York, N. Y. 10011. All rights reserved. This article cannot be reproduced for any purpose whatsoever without permission of the publisher. A cop)" of this article is available from the publisher for $t5.00.

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