Comparison of NMR water proton T1 relaxation times of rabbit tissues at 24 MHz and 2.5 MHz

Abstract

The ratios between T₁ relaxation times at 24 MHz and 2.5 MHz for most of the rabbit tissues lie in the range 1.9 to 2.2. However, among the rabbit tissues certain distinct types were found to have T₁ ratios different from those of the general range. In particular this is true of muscle and nervous tissue. The ratios for most striated muscles lie in the range 2.7 to 3.1. However, the range for smooth muscle, 2.0 to 2.2, is very similar to that of the majority of other tissues, whilst the ratio for cardiac muscle, 2.5+or-0.11, lies between the extremes of the other major muscle types. For nervous tissues the ratios are, in general, considerably below 2.0. Spinal cord has a ratio of 1.43+or-0.1; medulla oblongata (1.66+or-0.16), cerebellum (1.75+or-0.02) and the white matter of the cerebral hemisphere (possibly with some contaminating grey matter) (1.77+or-0.08) lie intermediate between the values for spinal cord and the grey matter of the cerebral hemisphere, this latter being 2.00+or-0.01. Other variations were noticeable, for example, the difference in the ratio seen between bile and blood serum and the low ratio of the salivary gland.