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Modulation of porcine heart sarcolemma lipids by dietary fish oll-CA2 transport and receptor function
j Mol Cell Cardiol 18 (Supplement 1) (1986)
333EFFECTS
OF KETANSERIN ON SEROTON-INDUCED CHANGE IN CYTOSOLIC CALCIUM CONCENTRATIONS IN VASCULAR SMOOTH MUSCLE CELLS. H.Kanaide, M.Hasegawa, S.Kobayashi, M.Nakamura. Res Inst Angiocardiol, Cardiovasc Clin, Faculty of Med, Kyushu Univ. Fukuoka, Japan. Using the microfluorometry of quin 2, we investigated the effect of ketanserin on serotonin-induced change in cytosolic free calcium concentrations (Ca)i in rat aorta vascular smooth muscle cells (VSMC) in primary culture. When the VSMC were exposed to serotonin either in normal PSS (i mM calcium) or in calcium-free media containing 2mM EGTA, there was a transient elevation of (Ca)i. (Ca)i increased rapidly to give the peak effect within 30 sec, and then, decreased gradually. The peak (Ca)i value was dose-dependent (between I0 -I0 M and IO-4M). (Ca)i was not affected at all b~ketanserin alone. When the VSMC were exposed to ketanserin in the presence of 5xlO-UM serotonin, there was a dose-dependent (between I 0 - I ~ and IO-4M) decrease in (Ca)i. Above the dose of IO -I0 M in normal PSS and 10-1214 in calcium-free media, (Ca)i became progressively lower than the pre-exposure levels. These results clearly demonstrate that predominant response of cultured rat VSMC to serotonin is an increase in (Ca)i. The abolition by ketanserin of the response of (Ca)i-increase to serotonin unmasked the response of (Ca)i-decrease to this monoamine.
334
THE EFFECT OF ERGONOVINE ON CYTOSOLIC CALCIUM CONCENTRATIONS IN CULTURED VASCULAR SMOOTH MUSCLE CELLS. H.Kanaide, M.Hasegawa, S.Kobayashi, M.Nakamura. Res Inst Angiocardiol, Cardiovasc Clin, Faculty of Med, Kyushu Univ. Fukuoka, Japan. Using an intracellularly trapped dye, quin 2, effects of erEonovine on cytosolic free calcium concentrations were recorded microfluorometrically in rat aorta v a s c u l ~ smooth muscle cells in primary culture. When the cells were exposed to IO--M ergonovine either in normal PSS(I mM calcium) or in calcium-free PSS containing 2 mM EGTA, there appeared a transient and double peaked elevation of cytosolic calcium concentration. There was a prOgressive increase in calcium concentration to give the first peak in 5 to 9 min, followed by a transient decrease in calcium to the level of 50% of the first peak in 9 to ii min. Calcium increased again to give the second peak at 20 min, followed by a gradual decrease to the pre-exposure level a~o40 min. The second peak was slightly higher than the first one. When ketanserin(lO -VM) was added to the media, I00~ and 50~ reduction of the first peaks were observed in the cells in normal and calcium-free media, respectively. Second peak was not affected at all in both normal and calcium free media. Thus, it was suggested that a part (the first peak) of an increase in cytosolic calcium concentration by ergonovine is due to activation of the serotonin receptor as an agonist.
335MODULATION OF P O R C I N E H E A R T S A R C O L E M M A L I P I D S BY D I E T A R Y F ~ H OIL-CA2+ T R A N S P O R T A N D R E C E P ~ Q R F U N C T I O N ; J . M . J . L a m e r s , L . v . d % ~ e r f - - , A. M o n t f o o r t - , J.M. H a r t o g - - , W.C. H ~ i s m a n n + a n d P.D. V e r d o u w +~ D e p a r t m e n t s of B i o c h e m i s t r y I, P a t h o l o g i c a l A n a t O m y and Thoraxcentre , Erasmus Univ e r s i t y R o t t e r d a m , R o t t e r d a m , The N e t h e r l a n d s . C h a n g e s in the f a t t y a c i d c o m p o s i t i o n of the p h o s p h o l i p i d b i l a y e r , in p a r t i c u l a r t h o s e of the p o l y u n s a t u r a t e d f a t t y a c i d s , are b e l i e v e d to be i m p o r t a n t to m e m b r a n e f u n c t i o n . A c o n c e n t r a t i o n of 9% (w / w ) m a c k e rel oil or l a r d f a t w a s a d d e d to a f a t p o o r d i e t of y o u n g pigs. A f t e r 8 w e e k s b i o p s i e s w e r e t a k e n f r o m the l e f t v e n t r i c l e a n d h o m o g e n a t e and m e m b r a n e f r a c t i o n s w e r e p r e p a r e d . F a t t y acid c o m p o s i t i o n of t o t a l p h o s p h o l i p i d f r a c t i o n s s h o w e d d r a m a t i c c h a n g e s in 18:2 ~ 6 , 2 0 : 4 ~ 6 , 20:5 ~ 3 and 22:6 ~ 3 c o n t e n t , w h e r e a s no c h a n g e s w e r e o b s e r v e d in the s a t u r a t e d f a t t y acids. M e m b r a n e d o u b l e b a n d i n d i c e s w e r e 1 . 2 8 and 1.85 in lard f a t and m a c k e r e l Oil f e d a n i m a l s , r e s p e c t i v e l y . N o d i e t - r e l a t e d d i f f e r e n c e s w e r e o b s e r v e d in the p r o p e r t i e s of the N a + / C a 2 + a n t i p o r t e r (spec i f i c a c t i v i t y and s t i m u l a t i o n by K+ d i f f u s i o n p o t e n t i a l ) . Ca2+ p u m p i n g A T P a s e ( s p e c i f i c activity) and 5 ' - n u c l e o t i d a s e ( s p e c i f i c activity) had s i g n i f i c a n t l y l o w e r a c t i v i t y in lard fed a n i m a l s . A d e n y l a t e c y c l a s e in h e a r t m e m b r a n e s f r o m m a c k e r e l o i l - f e d p i g s w a s m o r e s e n s i t i v e to i s o p r o t e r e n o l . S u p p o r t e d by the D u t c h H e a r t F o u n d a t i o n .
333EFFECTS
OF KETANSERIN ON SEROTON-INDUCED CHANGE IN CYTOSOLIC CALCIUM CONCENTRATIONS IN VASCULAR SMOOTH MUSCLE CELLS. H.Kanaide, M.Hasegawa, S.Kobayashi, M.Nakamura. Res Inst Angiocardiol, Cardiovasc Clin, Faculty of Med, Kyushu Univ. Fukuoka, Japan. Using the microfluorometry of quin 2, we investigated the effect of ketanserin on serotonin-induced change in cytosolic free calcium concentrations (Ca)i in rat aorta vascular smooth muscle cells (VSMC) in primary culture. When the VSMC were exposed to serotonin either in normal PSS (i mM calcium) or in calcium-free media containing 2mM EGTA, there was a transient elevation of (Ca)i. (Ca)i increased rapidly to give the peak effect within 30 sec, and then, decreased gradually. The peak (Ca)i value was dose-dependent (between I0 -I0 M and IO-4M). (Ca)i was not affected at all b~ketanserin alone. When the VSMC were exposed to ketanserin in the presence of 5xlO-UM serotonin, there was a dose-dependent (between I 0 - I ~ and IO-4M) decrease in (Ca)i. Above the dose of IO -I0 M in normal PSS and 10-1214 in calcium-free media, (Ca)i became progressively lower than the pre-exposure levels. These results clearly demonstrate that predominant response of cultured rat VSMC to serotonin is an increase in (Ca)i. The abolition by ketanserin of the response of (Ca)i-increase to serotonin unmasked the response of (Ca)i-decrease to this monoamine.
334
THE EFFECT OF ERGONOVINE ON CYTOSOLIC CALCIUM CONCENTRATIONS IN CULTURED VASCULAR SMOOTH MUSCLE CELLS. H.Kanaide, M.Hasegawa, S.Kobayashi, M.Nakamura. Res Inst Angiocardiol, Cardiovasc Clin, Faculty of Med, Kyushu Univ. Fukuoka, Japan. Using an intracellularly trapped dye, quin 2, effects of erEonovine on cytosolic free calcium concentrations were recorded microfluorometrically in rat aorta v a s c u l ~ smooth muscle cells in primary culture. When the cells were exposed to IO--M ergonovine either in normal PSS(I mM calcium) or in calcium-free PSS containing 2 mM EGTA, there appeared a transient and double peaked elevation of cytosolic calcium concentration. There was a prOgressive increase in calcium concentration to give the first peak in 5 to 9 min, followed by a transient decrease in calcium to the level of 50% of the first peak in 9 to ii min. Calcium increased again to give the second peak at 20 min, followed by a gradual decrease to the pre-exposure level a~o40 min. The second peak was slightly higher than the first one. When ketanserin(lO -VM) was added to the media, I00~ and 50~ reduction of the first peaks were observed in the cells in normal and calcium-free media, respectively. Second peak was not affected at all in both normal and calcium free media. Thus, it was suggested that a part (the first peak) of an increase in cytosolic calcium concentration by ergonovine is due to activation of the serotonin receptor as an agonist.
335MODULATION OF P O R C I N E H E A R T S A R C O L E M M A L I P I D S BY D I E T A R Y F ~ H OIL-CA2+ T R A N S P O R T A N D R E C E P ~ Q R F U N C T I O N ; J . M . J . L a m e r s , L . v . d % ~ e r f - - , A. M o n t f o o r t - , J.M. H a r t o g - - , W.C. H ~ i s m a n n + a n d P.D. V e r d o u w +~ D e p a r t m e n t s of B i o c h e m i s t r y I, P a t h o l o g i c a l A n a t O m y and Thoraxcentre , Erasmus Univ e r s i t y R o t t e r d a m , R o t t e r d a m , The N e t h e r l a n d s . C h a n g e s in the f a t t y a c i d c o m p o s i t i o n of the p h o s p h o l i p i d b i l a y e r , in p a r t i c u l a r t h o s e of the p o l y u n s a t u r a t e d f a t t y a c i d s , are b e l i e v e d to be i m p o r t a n t to m e m b r a n e f u n c t i o n . A c o n c e n t r a t i o n of 9% (w / w ) m a c k e rel oil or l a r d f a t w a s a d d e d to a f a t p o o r d i e t of y o u n g pigs. A f t e r 8 w e e k s b i o p s i e s w e r e t a k e n f r o m the l e f t v e n t r i c l e a n d h o m o g e n a t e and m e m b r a n e f r a c t i o n s w e r e p r e p a r e d . F a t t y acid c o m p o s i t i o n of t o t a l p h o s p h o l i p i d f r a c t i o n s s h o w e d d r a m a t i c c h a n g e s in 18:2 ~ 6 , 2 0 : 4 ~ 6 , 20:5 ~ 3 and 22:6 ~ 3 c o n t e n t , w h e r e a s no c h a n g e s w e r e o b s e r v e d in the s a t u r a t e d f a t t y acids. M e m b r a n e d o u b l e b a n d i n d i c e s w e r e 1 . 2 8 and 1.85 in lard f a t and m a c k e r e l Oil f e d a n i m a l s , r e s p e c t i v e l y . N o d i e t - r e l a t e d d i f f e r e n c e s w e r e o b s e r v e d in the p r o p e r t i e s of the N a + / C a 2 + a n t i p o r t e r (spec i f i c a c t i v i t y and s t i m u l a t i o n by K+ d i f f u s i o n p o t e n t i a l ) . Ca2+ p u m p i n g A T P a s e ( s p e c i f i c activity) and 5 ' - n u c l e o t i d a s e ( s p e c i f i c activity) had s i g n i f i c a n t l y l o w e r a c t i v i t y in lard fed a n i m a l s . A d e n y l a t e c y c l a s e in h e a r t m e m b r a n e s f r o m m a c k e r e l o i l - f e d p i g s w a s m o r e s e n s i t i v e to i s o p r o t e r e n o l . S u p p o r t e d by the D u t c h H e a r t F o u n d a t i o n .