Hippocampal volume in postmenopausal cynomolgus macaques with behavioral depression.
OBJECTIVE
Magnetic resonance imaging (MRI) studies report hippocampal (HC) volume reductions in depression. Despite observations of functional heterogeneity and ovarian steroid influence in the hippocampus, few studies report regional volume alterations or control for menstrual cycle phase. Using in vitro methods, we recently observed reduced anterior HC volume in antidepressant-naive, ovarian-intact, behaviorally depressed adult female monkeys. The purpose of this study was to confirm these findings in vivo and examine whether lack of ovarian steroids affects the relationship between depression and HC volume.


METHODS
MRI was used to measure whole, anterior, and posterior HC volumes in a matched sample of antidepressant-naive, surgically postmenopausal adult female cynomolgus macaques characterized for behavioral depression (six depressed, six nondepressed). High-resolution structural MRIs were acquired, and HC regions of interest were manually segmented. HC volumes were normalized to whole brain volumes before analysis.


RESULTS
Similar to the previous in vitro study, HC volume measured in vivo was associated with depression. In contrast to the previous study of ovarian-intact female monkeys, whole, anterior, and posterior volumes of both the left and right hippocampi were significantly smaller in depressed compared with nondepressed surgically postmenopausal female monkeys.


CONCLUSIONS
These findings confirm and extend previous observations of smaller HC volumes in behaviorally depressed female monkeys and suggest a possible role for ovarian steroids in HC protection in depression. Further studies of the potential modulating effects of ovarian function on the relationship between depression and HC volume are warranted.
Neuroscience Graduate Program, Graduate School of Arts and Sciences, School of Medicine, Wake Forest University, Winston-Salem, NC 27157, USA.
Stephanie L
SL
Willard
James B
JB
Daunais
J Mark
JM
Cline
Carol A
CA
Shively
D000818:Animals; D003863:Depression / Q000473:pathology*; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D008252:Macaca fascicularis; D008279:Magnetic Resonance Imaging; D009929:Organ Size; D017698:Postmenopause
J Affect Disord. 2003 Mar;74(1):5-13
12646294
Psychoneuroendocrinology. 2007 Sep-Nov;32(8-10):981-90
17768011
Psychoneuroendocrinology. 2009 Nov;34(10):1469-75
19493628
Biol Psychol. 2005 Apr;69(1):67-84
15740826
Biol Psychiatry. 1997 Apr 15;41(8):871-82
9099414
Front Neuroendocrinol. 2008 May;29(2):219-37
18078984
ASN Neuro. 2009 Nov 10;1(4):
19843010
J Comp Neurol. 1993 Oct 8;336(2):293-306
8245220
Neurosci Biobehav Rev. 2004 May;28(3):273-83
15225971
Neuroscience. 2007 Apr 25;146(1):60-8
17320294
Am J Psychiatry. 2008 Feb;165(2):229-37
17986679
Breast Cancer Res Treat. 2009 Mar;114(2):233-42
18404370
Brain Struct Funct. 2008 Sep;213(1-2):93-118
18704495
J Neurosci. 2010 Jan 13;30(2):431-8
20071507
Am J Primatol. 1991;23(4):239-245
31952398
Biol Psychiatry. 2005 Apr 15;57(8):935-7
15820716
Psychosom Med. 2002 Sep-Oct;64(5):699-706
12271100
J Comp Neurol. 2003 Oct 27;465(4):540-50
12975814
Hippocampus. 2008;18(10):985-8
18767068
Regul Toxicol Pharmacol. 2004 Jun;39(3):334-47
15135212
Neuroimage. 2008 Jan 15;39(2):832-46
17964814
Physiol Behav. 2009 May 25;97(2):239-49
19275910
Hum Brain Mapp. 2009 Nov;30(11):3719-35
19441021
Hippocampus. 1998;8(6):608-19
9882018
Endocrinology. 2003 Nov;144(11):4734-8
12960039
Behaviour. 1974;49(3):227-67
4597405