CSF-plasma relationships for DSIP and some other neuropeptides

The relationships between CSF and plasma hormonal levels of several peptides were studied in the same samples of simultaneously obtained plasma and CSF. A significant correlation existed between CSF and plasma levels of DSIP as well as gastrin. Preliminary results also showed a correlation between CSF and plasma levels of NT, but not VIP or calcitonin. CSF/plasma ratios and the effect of BBB disruption also varied from peptide to peptide. These diverse CSF/plasma relationships are not easily explained by models of nonspecific passage but may indicate individual systems or axes that could be involved in the central effects of peripherally administered peptides.