3 research outputs found
Vasoactive intestinal polypeptide promotes sleep without effects on brain temperature in rats at night
The possible sleep-promoting activity of vasoactive intestinal polypeptide (VIP) was contrasted with the
physiological sleep suppression in the diurnal active period through the i.c.v, injection of 100 ng VIP into
rats at dark onset. The sleep-wake activity and brain temperature (Tbr) were recorded for 24 h (dark period
and light period, 12 h each), and the effects were evaluated with respect to records obtained after artificial
cerbrospinal fluid injection. Without altering the normal course of Tbr, VIP induced a prompt and persistent increase of sleep. Wakefulness was significantly suppressed and non-REM sleep increased for 6 h, while
REM sleep increased for 3 h. The obvious sleep-promoting action of VIP, unrelated to thermoregutatory
effects, supports the notion that the peptide might be involved in sleep regulation