Phosphocreatine T1 measurements with and without exchange in the heart.
Phosphocreatine T1 measurements with and without exchange in the heart.
复制标题
有或没有心脏交换的磷酸肌酸 T1 测量。
DOI：
10.1002/mrm.1910300108
复制
发表时间：
1993
影响因子：
3.3
通讯作者：
Ingwall,JS
中科院分区：
文献类型：
--
作者：
Friedrich,J;Nascimben,L;Liao,R;Ingwall,JS
The intrinsic phosphocreatine (PCr)T1values measured by time‐dependent magnetization transfer in isolated perfused rat, hamster, and turkey hearts were indistinguishable. The value of 3.5 ± 0.3 s for the rat heart is similar to values measured by other magnetization transfer methods. Irreversibly inhibiting the phosphoryl exchange between PCr and ATP in the rat heart using iodoacetamide changed the apparentT1values of the two exchanging species when measured by inversion recovery: The apparentT1of PCr increased from 1.92 ± 0.06 s to 3.55 ± 0.06 s, in excellent agreement with the intrinsicT1, measured by magnetization transfer. The apparentT1of [γ‐P]ATP decreased from 0.92 ± 0.07 s to 0.44 ± 0.03 s. The value for theT1of [γ‐P]ATP in hearts with inhibited phosphoryl exchange was similar toT1values for [α‐P]ATP and [β‐P]ATP, which remained unchanged. This illustrates that apparentT1values for PCr and [γ‐P]ATP measured by inversion recovery in the presence of exchange are averageT1values in between the intrinsic values. The large differences between the intrinsicT1measured by magnetization transfer and theT1measured by inversion recovery makes the use of the appropriate value in different applications quantitatively important.
