Masumura M, Yamaguchi M, Shirakuni T, Nagashima T, Tamaki N, Matsumoto S, Sugiura M
No To Shinkei. 1984 Aug;36(8):805-11.
Using rat brains, the maturational change on the water contents and on the proton NMR signals were studied in this laboratory. Water contents, the proton longitudinal relaxation time (T1) and the transverse relaxation time (T2) were measured on the samples from gray and white matters, separately. A constant decrease of these parameter values was observed in relation to the development of the brain. Water content of 1 week-old rat was 88.393 +/- 1.19% in the gray matter (G) and 88.63 +/- 1.96% in the white matter (W). These values decreased gradually and reached adult rat level when the animals became 5 weeks old: 81.47 +/- 1.67% in G and 79.45 +/- 2.39% in W. No marked change on the brain water content was observed thereafter, T1 values of immature (one week-old) rat brain were 1.755 +/- 0.088 sec in G, and 1.832 +/- 0.154 sec in W, while T1 values of the adult rat brain were 1.327 +/- 0.043 sec in G, and 1.297 +/- 0.039 sec in W, respectively. A marked difference was observed on the values of T1 between the immature and the adult rats. T2 value of the 1 week-old rat brain was 101.05 +/- 10.20 msec in G, and 102.75 +/- 8.10 msec in W, respectively. T2 of the mature rat brain was 56.90 +/- 2.61 msec in G, and 54.52 +/- 2.35 msec in W, respectively. A statistically significant correlation was proved between the water content and the proton relaxation time (either T1 and T2).(ABSTRACT TRUNCATED AT 250 WORDS)
本实验室利用大鼠脑研究了水分含量和质子核磁共振信号的成熟变化。分别测量了灰质和白质样本的水分含量、质子纵向弛豫时间（T1）和横向弛豫时间（T2）。观察到这些参数值随脑发育持续下降。1周龄大鼠灰质（G）的水分含量为88.393±1.19%，白质（W）为88.63±1.96%。这些值逐渐降低，在动物5周龄时达到成年大鼠水平：G为81.47±1.67%，W为79.45±2.39%。此后未观察到脑含水量有明显变化。未成熟（1周龄）大鼠脑的T1值在G中为1.755±0.088秒，在W中为1.832±0.154秒，而成年大鼠脑的T1值在G中为1.327±0.043秒，在W中为1.297±0.039秒。未成熟和成年大鼠的T1值存在显著差异。1周龄大鼠脑的T2值在G中分别为101.05±10.20毫秒，在W中为102.75±8.10毫秒。成熟大鼠脑的T2在G中为56.90±2.61毫秒，在W中为54.52±2.35毫秒。水分含量与质子弛豫时间（T1和T2）之间存在统计学显著相关性。（摘要截选至250字）
