Alcohol preference in mice lacking the Avpr1a vasopressin receptor.
[Arg(8)]-vasopressin (Avp), a nonapeptide hormone, is known to regulate blood pressure, water balance, and a variety of behaviors such as anxiety, aggression, and bonding. Although some evidence that Avp modifies ethanol consumption and some of the effects of ethanol on behavior have been reported, the role of Avp in alcohol consumption and preference is poorly understood. The Avp1a receptor (Avpr1a) is ubiquitously expressed in the central nervous system. To determine the role of Avp signaling on the behavioral effects of alcohol, we examined voluntary ethanol consumption in mice with targeted disruptions of the Avpr1a knockout (Avpr1a KO) gene. Avpr1a KO mice displayed both increased ethanol consumption and preference compared with wild-type (WT) mice. Enhanced ethanol consumption was dramatically and reversibly reduced by treatment with N-methyl-D-aspartic acid antagonists. Basal glutamate release was elevated around the striatum in Avpr1a KO mice. Elevation of extracellular glutamate was also produced in WT mice by local application of an Avpr1a antagonist though a dialysis probe, and this elevation was quickly reversed by stopping the perfusion. These results suggest that Avp can inhibit the release of glutamate from the presynaptic terminal via the Avp1a receptor and that elevation of glutamate levels owing to loss of the inhibitory effect via Avp-Avpr1a signaling may play an important role in the preference for ethanol.
Sanbe
Atsushi
A
Department of Pharmacology, National Research Institute for Child Health and Development, Tokyo, Japan. asanbe@nch.go.jp
Takagi
Norio
N
Fujiwara
Yoko
Y
Yamauchi
Junji
J
Endo
Toshiya
T
Mizutani
Reiko
R
Takeo
Satoshi
S
Tsujimoto
Gozoh
G
Tanoue
Akito
A
D000428:Alcohol Drinking / Q000235:genetics* / Q000523:psychology*; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D002492:Central Nervous System Depressants / Q000097:blood; D016291:Dizocilpine Maleate / Q000494:pharmacology; D000431:Ethanol / Q000097:blood; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005110:Extracellular Space / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009271:Naltrexone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis / Q000235:genetics; D017483:Receptors, Vasopressin / Q000235:genetics*; D012727:Sex Characteristics
D000596:Amino Acids; D002492:Central Nervous System Depressants; D018691:Excitatory Amino Acid Antagonists; D009292:Narcotic Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D017483:Receptors, Vasopressin; D001127:Arginine Vasopressin; D000431:Ethanol; D018698:Glutamic Acid; D009271:Naltrexone; D016291:Dizocilpine Maleate