Abstract
In several species DSIP at low doses has been shown to promote sleep. Although its physiological role remains to be clarified, DSIP illustrates several concepts applicable to other brain peptides. These include the bell-shaped dose-response curve, central effects after peripheral administration, a delayed and prolonged time course, and some penetration of the blood-brain barrier in essentially intact form. Concepts applicable to one neuropeptide, therefore, appear to be applicable to others. In this article Abba Kastin and colleagues review the known effects of DSIP and argue that more work needs to be carried out before it can be labelled functionally.
