AGE-INDUCED DECREASES IN THE MESSENGER-RNA CODING FOR THE SARCOPLASMIC-RETICULUM CA-2+-ATPASE OF THE RAT-HEART

被引:72
作者
MACIEL, LMZ [1 ]
POLIKAR, R [1 ]
ROHRER, D [1 ]
POPOVICH, BK [1 ]
DILLMANN, WH [1 ]
机构
[1] UNIV CALIF SAN DIEGO, MED CTR, DEPT MED, 225 DICKINSON ST, H-811-C, SAN DIEGO, CA 92103 USA
关键词
age effects; Ca[!sup]2+[!/sup]-ATPase; sarcoplasmic reticulum;
D O I
10.1161/01.RES.67.1.230
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
Age-associated slowing of cardiac relaxation related to the decline in the Ca2+ pump function of cardiac sarcoplasmic reticulum (SR) has been previously described. It is unclear if the decreased Ca2+ pump function results from a lower amount of Ca2+-ATPase protein or a decreased pumping activity of the enzyme. To determine if these alterations could be mediated by changes in the amount of the protein itself, the level of the messenger RNA (mRNA) coding for the Ca2+-ATPase of the SR of Fischer rat hearts (4- and 30-month-old rats) were quantitated with a Northern blotting technique. We observed that the levels of SR Ca2+-ATPase mRNA were 60% lower in old rats as compared with young rats, suggesting that a quantitative reduction in the levels of the corresponding protein could occur during aging to explain the delayed diastolic relaxation documented in old animals as opposed to a change in the specific activity of this enzyme. The thyroid hormone responsiveness of SR Ca2+-ATPase mRNA has been previously established. We have found in this study that the thyroxine levels were consistently lower in old rats; however, this difference was relatively small (4.3 ± 0.7 and 3.1 ± 0.8 μg/dl [mean ± SD], respectively, in young and old rats). In addition, no age-induced decrease in 3,5,3'-triiodothyronine levels was observed, suggesting that the aging process itself may be responsible for the changes in SR Ca2+-ATPase mRNA levels.
引用
收藏
页码:230 / 234
页数:5
相关论文
共 22 条
[1]   EFFECTS OF AGE AND OVARIAN-FUNCTION ON PITUITARY-THYROID SYSTEM IN FEMALE RATS [J].
CHEN, HJ ;
WALFISH, PG .
JOURNAL OF ENDOCRINOLOGY, 1978, 78 (02) :225-232
[2]  
DILLMANN WH, 1983, J BIOL CHEM, V258, P7738
[3]  
FELICETTA JV, 1988, ENDOCRINOLOGY AGING, P15
[4]  
Fisher D. A., 1974, HDB PHYSIOLOGY 7, VIII, P21
[5]   STUDIES OF SARCOPLASMIC-RETICULUM FUNCTION AND CONTRACTION DURATION IN YOUNG-ADULT AND AGED RAT MYOCARDIUM [J].
FROEHLICH, JP ;
LAKATTA, EG ;
BEARD, E ;
SPURGEON, HA ;
WEISFELDT, ML ;
GERSTENBLITH, G .
JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY, 1978, 10 (05) :427-438
[6]   HEMODYNAMICS AND ITS REGULATION IN OLD-AGE [J].
FROLKIS, VV ;
BEZRUKOV, VV ;
SHEVCHUK, VG .
EXPERIMENTAL GERONTOLOGY, 1975, 10 (05) :251-271
[7]   THYROID AND AGE [J].
FROLKIS, VV ;
VERZHIKOVSKAYA, NV ;
VALUEVA, GV .
EXPERIMENTAL GERONTOLOGY, 1973, 8 (05) :285-296
[8]  
GOLDBERG P, 1978, AGING-US, V6, P87
[9]   RELATION OF AGE TO DURATION OF CONTRACTION EJECTION + RELAXATION OF NORMAL HUMAN HEART [J].
HARRISON, TR ;
COLEMAN, HN ;
BIDWAI, PS ;
RUSSELL, RO ;
DIXON, K .
AMERICAN HEART JOURNAL, 1964, 67 (02) :189-&
[10]   NUCLEOTIDE-SEQUENCE OF FULL LENGTH CDNAS ENCODING RAT CARDIAC MYOSIN LIGHT CHAIN-2 [J].
HENDERSON, SA ;
XU, YC ;
CHIEN, KR .
NUCLEIC ACIDS RESEARCH, 1988, 16 (10) :4722-4722