Journal of Neuroscience, Vol 2, 674-680, Copyright © 1982 by Society for Neuroscience
Temporal patterns of somatostatin immunoreactivity in the cerebrospinal fluid of the rhesus monkey: effect of environmental lighting
MA Arnold, SM Reppert, OP Rorstad, SM Sagar, HT Keutmann, MJ Perlow and JB Martin
A rabbit antiserum to somatostatin was used to develop radioimmunoassay
methods for measuring somatostatin in monkey cerebrospinal fluid (CSF). By
gel permeation chromatography, at least five molecular weight forms of
immunoreactive somatostatin (IRS) were identified in monkey CSF; two of
these species co-migrated with either synthetic somatostatin-14 or
somatostatin-28. The 24-hr profile of CSF somatostatin immunoreactivity was
obtained from five monkeys during diurnal lighting, constant light, and
constant darkness. During diurnal lighting, all five monkeys had a clear
ultradian component in CSF IRS of 4 to 5 hr duration; this pattern was not
affected significantly by constant light or dark. In addition, there of the
five monkeys exposed to diurnal lighting showed a diurnal rhythm in CSF
IRS, with higher hormone levels during darkness. In some animals, this
diurnal rhythm also could be demonstrated during constant light or dark.