Ameliorative effect of vasopressin-(4-9) through vasopressin V(1A) receptor on scopolamine-induced impairments of rat spatial memory in the eight-arm radial maze

Eur J Pharmacol. 2001 Sep 7;427(1):43-52. doi: 10.1016/s0014-2999(01)01200-6.

Abstract

In order to clarify the mechanism by which pGlu-Asn-Cys(Cys)-Pro-Arg-Gly-NH(2) (vasopressin-(4-9)), a major metabolite C-terminal fragment of [Arg(8)]-vasopressin (vasopressin-(1-9)), improves learning and memory, we used several different drugs such as an acetylcholine receptor antagonist, a Ca(2+)/calmodulin-dependent protein kinase II inhibitor, vasopressin receptor antagonists and L-type Ca(2+) channel blocker to disrupt spatial memory in rats. Moreover, we examined the effect of vasopressin-(4-9) on acetylcholine release in the ventral hippocampus using microdialysis. Vasopressin-(4-9) (10 fg/brain, i.c.v.) improved the impairment of spatial memory in the eight-arm radial maze induced by scopolamine, pirenzepine and Ca(2+)/calmodulin -dependent protein kinase II inhibitor. Pirenzepine, a vasopressin V(1A) receptor antagonist, and L-type Ca(2+) channel blocker, but not a vasopressin V(2) receptor antagonist, suppressed the effects of vasopressin-(4-9) on scopolamine-induced impairment of spatial memory. Moreover, vasopressin-(4-9) did not affect acetylcholine release in the ventral hippocampus of intact rats or of scopolamine-treated rats as assessed by microdialysis. These results suggest that vasopressin-(4-9) activates vasopressin V(1A) receptors on the postsynaptic membrane of cholinergic neurons, and induces a transient influx of intracellular Ca(2+) through L-type Ca(2+) channels to interact with muscarinic M(1) receptors. The activation of these processes by vasopressin-(4-9) is critically involved in the positive effect of vasopressin-(4-9) on scopolamine-induced impairment of spatial memory.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / analogs & derivatives
  • 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / pharmacology
  • Acetylcholine / metabolism
  • Animals
  • Antidiuretic Hormone Receptor Antagonists
  • Arginine Vasopressin / analogs & derivatives
  • Arginine Vasopressin / chemistry
  • Arginine Vasopressin / pharmacology
  • Benzazepines / pharmacology
  • Calcium Channel Blockers / pharmacology
  • Dose-Response Relationship, Drug
  • Hemicholinium 3 / pharmacology
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Hormone Antagonists / pharmacology
  • Injections, Intraventricular
  • Male
  • Maze Learning / drug effects*
  • Memory / drug effects*
  • Memory Disorders / chemically induced
  • Memory Disorders / prevention & control
  • Neurotransmitter Uptake Inhibitors / pharmacology
  • Nicardipine / pharmacology
  • Peptide Fragments / pharmacology*
  • Pirenzepine / pharmacology
  • Rats
  • Rats, Wistar
  • Receptors, Vasopressin / physiology*
  • Scopolamine / pharmacology*

Substances

  • Antidiuretic Hormone Receptor Antagonists
  • Benzazepines
  • Calcium Channel Blockers
  • Hormone Antagonists
  • Neurotransmitter Uptake Inhibitors
  • Peptide Fragments
  • Receptors, Vasopressin
  • vasopressin, 1-(2-mercapto-2,2-(cyclopentamethylene)propionic acid)-2-(O-methyl)Tyr-8-Arg-
  • Arginine Vasopressin
  • mozavaptan
  • Hemicholinium 3
  • Pirenzepine
  • KN 62
  • 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine
  • Nicardipine
  • Scopolamine
  • Acetylcholine