title: Interactions between brainstem noradrenergic neurons and the nucleus accumbens shell in modulating memory for emotionally arousing events.
abstract: The nucleus accumbens shell (NAC) receives axons containing dopamine-β-hydroxylase that originate from brainstem neurons in the nucleus of the solitary tract (NTS). Recent findings show that memory enhancement produced by stimulating NTS neurons after learning may involve interactions with the NAC. However, it is unclear whether these mnemonic effects are mediated by norepinephrine (NE) release from NTS terminals onto NAC neurons. The present studies approached this question by examining the contribution of NAC α-noradrenergic receptors in mediating this effect and assessed whether glutamatergic activation of the NTS alters NE concentrations in the NAC. Rats were trained for 6 d to drink from a water spout located at the end of an inhibitory avoidance chamber. On day 7, a 0.35-mA footshock was initiated once the rat approached the spout and remained active until it escaped into the neutral compartment. Blockade of α-noradrenergic receptors in the NAC with phentolamine (0.5 µg/0.5 µL) attenuated memory enhancement produced by glutamatergic (50 ng/0.5 µL) infusion on NTS neurons (P < 0.01). Experiment 2 used in vivo microdialysis to assess whether glutamate activation of NTS alters NAC NE concentrations. NE levels were unchanged by NTS infusion of phosphate-buffered saline (PBS) or low dose glutamate (50 ng/0.5 µL) but elevated significantly (P < 0.05) by combining the same dose with the footshock (0.35 mA, 2 sec) given in Study 1 or infusion of (100 ng/0.5 µL) glutamate alone. Findings demonstrate that NE released from NTS terminals enhances representations in memory by acting on α-noradrenergic receptors within the NAC.
authors: Department of Psychology, Graduate Program in Neuroscience, University of Virginia, Charlottesville, Virginia 22904, USA. clw3b@virginia.edu
authors: Erin C
authors: EC
authors: Kerfoot
authors: Cedric L
authors: CL
authors: Williams
references: Neuroscience. 2003;119(1):19-31
references: 12763065
references: Synapse. 1997 Nov;27(3):230-41
references: 9329158
references: Prog Neurobiol. 1980;14(2-3):69-97
references: 6999537
references: Behav Brain Res. 1987 Jul;25(1):49-61
references: 3620086
references: Behav Neurosci. 2004 Feb;118(1):79-88
references: 14979784
references: Am J Physiol. 1997 Dec;273(6):R2080-8
references: 9435664
references: Behav Neurosci. 2002 Feb;116(1):13-21
references: 11895175
references: Brain Res. 1990 Apr 16;513(2):329-34
references: 2350704
references: Braz J Med Biol Res. 1997 Aug;30(8):967-70
references: 9361726
references: J Hypertens. 1995 Jun;13(6):631-5
references: 7594420
references: Neurochem Res. 1984 Sep;9(9):1231-8
references: 6095129
references: Behav Neurosci. 1998 Dec;112(6):1414-22
references: 9926823
references: Prog Brain Res. 1991;88:323-30
references: 1667547
references: Exp Physiol. 1994 Mar;79(2):265-8
references: 7911674
references: Behav Neurosci. 1994 Dec;108(6):1107-18
references: 7893403
references: Neuroscience. 1987 Oct;23(1):103-20
references: 3683859
references: J Neurochem. 2007 Mar;100(5):1247-56
references: 17241132
references: Brain Res. 1984 Mar;319(1):69-101
references: 6324960
references: Learn Mem. 2005 May-Jun;12(3):296-301
references: 15930508
references: Behav Neurosci. 2000 Dec;114(6):1131-44
references: 11142645
references: Neuroscience. 2000;98(4):743-7
references: 10891617
references: Neurobiol Learn Mem. 1999 Mar;71(2):232-9
references: 10082642
references: Biol Psychiatry. 1999 Nov 1;46(9):1140-52
references: 10560021
references: J Neurosci. 1996 Mar 1;16(5):1591-604
references: 8774428
references: Neuroscience. 2009 Feb 18;158(4):1284-91
references: 19041693
references: Synapse. 1999 Mar 1;31(3):196-202
references: 10029237
references: Learn Mem. 2008 Aug 26;15(9):643-8
references: 18772251
references: Neurobiol Learn Mem. 2010 Oct;94(3):303-11
references: 20650329
references: Brain Res. 1998 Sep 28;806(2):127-40
references: 9739125
references: J Neurosci Methods. 1980 Dec;3(2):129-49
references: 6110810
references: Neurobiol Learn Mem. 2008 Jan;89(1):47-60
references: 17964820
references: Brain Res. 2006 Nov 13;1119(1):124-32
references: 16962076
references: Eur J Neurosci. 2006 Nov;24(10):2781-8
references: 17156204
references: J Comp Neurol. 2000 May 1;420(2):211-32
references: 10753308
references: J Comp Neurol. 1993 Dec 8;338(2):255-78
references: 8308171
references: Behav Brain Res. 2004 Aug 12;153(1):87-95
references: 15219710
references: Neuroscience. 2010 Aug 11;169(1):132-42
references: 20451589
references: Brain Res. 1987 Aug 4;417(1):108-17
references: 3620971
references: Acta Pharmacol Sin. 2004 Mar;25(3):271-5
references: 15000876
references: Chin J Physiol. 1995;38(2):81-91
references: 8697902
references: Learn Mem. 2009 Sep 30;16(10):625-34
references: 19794188
references: Brain Res. 1982 Jun 3;241(1):123-30
references: 6286040
references: Psychopharmacology (Berl). 2010 Sep;211(4):479-91
references: 20602088
references: Neurobiol Learn Mem. 2008 Oct;90(3):576-9
references: 18657626
references: J Neurophysiol. 1998 Apr;79(4):1768-76
references: 9535946
references: Neurobiol Learn Mem. 2006 Mar;85(2):116-24
references: 16230035
references: Neuroscience. 2009 Dec 1;164(2):415-23
references: 19720115
references: Neuroscience. 2010 Feb 17;165(4):1370-6
references: 19958817
references: J Comp Neurol. 1996 Oct 21;374(3):387-420
references: 8906507
references: Behav Brain Res. 2000 Jul;112(1-2):151-8
references: 10862946
references: Brain Res. 1992 Apr 24;578(1-2):347-50
references: 1380865
references: Proc Natl Acad Sci U S A. 1984 Mar;81(5):1585-9
references: 6324206