Vasoactive intestinal peptide and gastrin-releasing peptide play distinct roles in the suprachiasmatic nucleus.
Vasoactive intestinal peptide and gastrin-releasing peptide levels were measured in the punched-out suprachiasmatic nucleus tissue from rats kept under a prolonged dim light (in vivo). Vasoactive intestinal peptide content increased from 4 to 8 h, returned to the baseline level at 12 to 16 h, and then increased again until 36 h after the light was switched off (dim light). Gastrin-releasing peptide level, in contrast, showed no significant changes, but a slight decrease from 1 to 4 h was detected under the dim light. In suprachiasmatic nucleus explant-slice culture, in vitro, Arg-vasopressin release increased transiently or showed a decrease at 30 min after exposure to vasoactive intestinal peptide or gastrin-releasing peptide, respectively. Treatment with anti-vasoactive intestinal peptide and anti-gastrin-releasing peptide antibodies reversed these effects. These findings suggest reciprocal roles of vasoactive intestinal peptide and gastrin-releasing peptide in Arg-vasopressin release.
Isobe
Y
Y
Department of Physiology, Nagoya City University Medical School, Japan.
Nishino
H
H
D000818:Animals; D046508:Culture Techniques; D019886:Gastrin-Releasing Peptide; D008297:Male; D009479:Neuropeptides / Q000502:physiology*; D010455:Peptides / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000502:physiology*
D009479:Neuropeptides; D010455:Peptides; D014660:Vasoactive Intestinal Peptide; D019886:Gastrin-Releasing Peptide