S-100 protein in adipose tissue.

1. The nervous system-specific S-100 protein is present at high levels in adipose tissues of various animal species. 2. The adipose S-100 protein levels in beef and rat were 1.13 and 1.59 micrograms/mg protein, respectively, which were comparable to the brain levels (beef, 4.85 micrograms/mg; rat, 1.98 micrograms/mg). 3. Adipose tissues of rabbit, pig and human contained 0.222, 0.149 and 0.083 micrograms S-100 protein/mg, respectively. 4. The S-100 protein level in rat adipose tissue showed a developmental profile similar to that in the brain.