[A study of the expression of sarcoplasmic reticulum calcium ATP-ase gene in the left ventricle of the sheep's fetus submitted to chronic increased afterload in utero].
The messenger RNA of the cardiac sarcoplasmic reticulum ATP-ase (SERCA-2a) increases in the left ventricle (LV) during ontogenic development but decreases in hypertrophy induced by increased afterload. Because of the frequency of increased left ventricular overload in congenital heart disease, the authors investigated to see if these increases were likely to interfere with the normal ontogenic program of expression of the SERCA-2a gene in the LV of sheep's foetus. A preductal coarctation of the aorta was realised by banding the transverse aorta (AoT) at 93 days' gestation in 9 foetus (CoA) matched with 9 healthy twin foetus (T). All the foetus underwent haemodynamic, anatomical, histological and molecular biological investigations 4 weeks later. The concentration of SERCA-2a mRNA in the LV was measured by hybridation of a Northern blot with a rat DNAc probe normalised with RNAr 18S. A coarctation was observed in all the CoA group and in none of the T. The ratio of LV weight/body weight was increased in 65% of CoA (p < 0.0001). The concentration of SERCA-2a mRNA in the LV was much reduced in CoA (average -28.6%) of the values observed in T (p = 0.003). Left ventricular hypertrophy of the sheep's foetus induced by pathological increases of afterload surpassed or slowed down the physiological ontogenic maturation of expression of the SERCA-2a gene in abnormalities of cardiac pump function.
Bonnet
N
N
Laboratoire de chirurgie expérimentale, Centre chirurgical Maria-Lannelongue, Le Plessis-Robinson.
Serraf
A
A
Samson
F
F
Heimburger
M
M
Mercadier
J J
JJ
Planché
C
C
D000818:Animals; D001017:Aortic Coarctation / Q000209:etiology / Q000503:physiopathology; D015152:Blotting, Northern; D000252:Calcium-Transporting ATPases / Q000235:genetics* / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D005318:Fetal Heart / Q000473:pathology / Q000601:surgery*; D018507:Gene Expression Regulation, Developmental; D006352:Heart Ventricles / Q000201:enzymology; D006439:Hemodynamics; D017682:Myocardial Stunning / Q000503:physiopathology*; D011247:Pregnancy; D012519:Sarcoplasmic Reticulum / Q000201:enzymology*; D012756:Sheep; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology
D000252:Calcium-Transporting ATPases