MYOINOSITOL TRANSPORT AND METABOLISM IN FETAL-BOVINE AORTIC ENDOTHELIAL-CELLS

被引:15
作者
BERRY, GT
JOHANSON, RA
PRANTNER, JE
STATES, B
YANDRASITZ, JR
机构
[1] Div. Biochemical Devel. Molec. Dis., Department of Pediatrics, Univ. Pennsylvania School Medicine, Philadelphia
关键词
D O I
10.1042/bj2950863
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The myo-inositol transport system in confluent fetal-bovine aortic endothelial cells was characterized after 7-10 days in subculture, at which time the myo-inositol levels and rates of myo-[2-H-3]-inositol uptake and incorporation into phospholipid had reached steady state. Kinetic analysis indicated that the uptake occurred by both a high-affinity transport system with an apparent K(t) of 31 muM and V(max) of 45 pmol/min per mg of protein, and a non-saturable low-affinity system. Uptake was competitively inhibited by phlorrhizin, with a K(i) of 50 muM; phloretin was a non-competitive inhibitor, with half-maximal inhibition between 0.2 and 0.5 mM. Glucose was a weak competitive inhibitor, with a K(i) of 37 mM; galactose failed to inhibit uptake. A weak dependence on Na+ for the initial rate of uptake was observed at 11 muM myo-inositol. When fetal-bovine-serum (FBS)-supplemented medium, which contained 225 muM myoinositol, was used, the cells contained about 200 nmol of myoinositol/mg of DNA. With adult-bovine-serum (ABS)supplemented medium, which contained 13 muM myo-inositol, the cells contained about 110 nmol/mg of DNA. Transport of 11 muM myo-[2-H-3]inositol was 18 and 125 pmol/min per mg of DNA for cells grown in FBS and ABS respectively. Kinetic analysis showed that for the cells grown in FBS the V(max) of the high-affinity system was decreased by 64%, whereas the K(t) remained essentially unchanged. Increased cell myo-inositol levels were not associated with an increased rate of phosphatidylinositol synthesis. After prolonged exposure of fetal endothelial cells to a myo-inositol concentration which approximated to a high fetal as opposed to a low adult blood level, cell myo-inositol levels doubled and high-affinity transport underwent down-regulation.
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页码:863 / 869
页数:7
相关论文
共 32 条
[1]   FREE MYO-INOSITOL CONCENTRATION OF ADULT AND FETAL TISSUES OF SEVERAL SPECIES [J].
BATTAGLIA, F ;
BLECHNER, JN ;
MESCHIA, G ;
BARRON, DH .
QUARTERLY JOURNAL OF EXPERIMENTAL PHYSIOLOGY AND COGNATE MEDICAL SCIENCES, 1961, 46 (02) :188-&
[2]   DISTRIBUTION AND PROPERTIES OF CDP-DIGLYCERIDE - INOSITOL TRANSFERASE FROM BRAIN [J].
BENJAMINS, JA ;
AGRANOFF, BW .
JOURNAL OF NEUROCHEMISTRY, 1969, 16 (04) :513-+
[3]   ACTIVE-TRANSPORT OF MYOINOSITOL IN RAT PANCREATIC-ISLETS [J].
BIDEN, TJ ;
WOLLHEIM, CB .
BIOCHEMICAL JOURNAL, 1986, 236 (03) :889-893
[4]   CHANGES IN CDP-DIGLYCERIDE-INOSITOL TRANSFERASE-ACTIVITY DURING RABBIT LUNG DEVELOPMENT [J].
BLEASDALE, JE ;
WALLIS, P ;
MACDONALD, PC ;
JOHNSTON, JM .
PEDIATRIC RESEARCH, 1979, 13 (10) :1182-1183
[5]  
BLEASDALE JE, 1981, BIOCHEM J, V206, P43
[6]  
CAPPLING JD, 1954, J PHYS LONDON, V126, P71
[7]  
COTLIER E, 1970, INVEST OPHTH VISUAL, V9, P681
[8]   DISTRIBUTION OF FREE MESOINOSITOL IN MAMMALIAN TISSUES, INCLUDING SOME OBSERVATIONS ON LACTATING RAT [J].
DAWSON, RM ;
FREINKEL, N .
BIOCHEMICAL JOURNAL, 1961, 78 (03) :606-+
[9]   SORBITOL, MYOINOSITOL, AND ROD OUTER SEGMENT PHAGOCYTOSIS IN CULTURED HRPE CELLS EXPOSED TO GLUCOSE - INVITRO MODEL OF MYOINOSITOL DEPLETION HYPOTHESIS OF DIABETIC COMPLICATIONS [J].
DELMONTE, MA ;
RABBANI, R ;
DIAZ, TC ;
LATTIMER, SA ;
NAKAMURA, J ;
BRENNAN, MC ;
GREENE, DA .
DIABETES, 1991, 40 (10) :1335-1348
[10]   A GENERAL, FAST, AND SENSITIVE MICROMETHOD FOR DNA DETERMINATION - APPLICATION TO RAT AND MOUSE-LIVER, RAT HEPATOMA, HUMAN-LEUKOCYTES, CHICKEN FIBROBLASTS, AND YEAST-CELLS [J].
FISZERSZAFARZ, B ;
SZAFARZ, D ;
DEMURILLO, AG .
ANALYTICAL BIOCHEMISTRY, 1981, 110 (01) :165-170