title: Dizocilpine and cycloheximide prevent inhibition of c-Fos gene expression by delta sleep-inducing peptide in the paraventricular nucleus of the hypothalamus in rats with different resistance to emotional stress.
abstract: The effects of the non-competitive NMDA-receptor blocker MK-801 (dizocilpine) and the protein synthesis inhibitor cycloheximide on the delta sleep-inducing peptide (DSIP) inhibition of c-Fos immediate early gene expression were studied in the parvocellular subdivision of the hypothalamic paraventricular nucleus (pPVN) of male Wistar rats with either high or low resistance to emotional stress, predicted from differences in their open-field behaviour. The experiments show that intraperitoneal (i.p.) DSIP injection (60 nmol/kg) decreased the number of Fos-immunoreactive (Fos-IR) cells in the pPVN, activated by immobilization. The NMDA-receptor antagonist dizocilpine (MK-801) (90 nmol i.c.v.) prevented the inhibition of c-Fos expression by DSIP in the pPVN of rats predisposed to emotional stress. The protein synthesis inhibitor cycloheximide (210 nmol i.c.v.) prevented the inhibition of c-Fos expression by DSIP in the pPVN of rats that were resistant to emotional stress. The experiments indicate that the DSIP effect on c-Fos gene expression might be mediated by NMDA-receptors. DSIP may induce production of some protein transcription factors, transmitting a signal from membrane NMDA-receptors to the nucleus.
authors.affiliation: P.K. Anokhin Institute of Normal Physiology, Russian Academy of Medical Sciences, Mohovaya, 11, Str. 4, 125009 Moscow, Russia. pavelum@mail.ru
authors.forename: P E
authors.initials: PE
authors.lastname: Umriukhin
authors.forename: E V
authors.initials: EV
authors.lastname: Koplik
authors.forename: K V
authors.initials: KV
authors.lastname: Sudakov
mesh_terms: D000818:Animals; D003513:Cycloheximide / Q000494:pharmacology; D003701:Delta Sleep-Inducing Peptide / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects*; D016762:Genes, fos / Q000187:drug effects / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D018696:Neuroprotective Agents / Q000494:pharmacology; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D012149:Restraint, Physical; D015398:Signal Transduction / Q000502:physiology; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D018696:Neuroprotective Agents; D011500:Protein Synthesis Inhibitors; D016760:Proto-Oncogene Proteins c-fos; D016194:Receptors, N-Methyl-D-Aspartate; D003701:Delta Sleep-Inducing Peptide; D016291:Dizocilpine Maleate; D003513:Cycloheximide