Beta-endorphin levels in longtailed and pigtailed macaques vary by abnormal behavior rating and sex.
Frequent or severe abnormal behavior may be associated with the release of endorphins that positively reinforce the behavior with an opiate euphoria or analgesia. One line of research exploring this association involves the superhormone, proopiomelanocortin (POMC). The products of POMC appear to be dysregulated in some human subjects who exhibit self-injurious behavior (SIB). Macaque monkeys have POMC very similar to humans, and some laboratory macaques display SIB or frequent stereotypies. We investigated associations between plasma levels of three immunoreactive POMC fragments with possible opioid action and abnormal behavior ratings in macaques. In 58 adult male and female macaques (24 Macaca fascicularis and 34 Macaca nemestrina), plasma levels of intact beta-endorphin (betaE) and the N-terminal fragment (BEN) were significantly higher in animals with higher levels of abnormal behavior. The C-terminal fragment (BEC) was significantly higher in males but unrelated to ratings of abnormal behavior. Levels of ACTH, cortisol, and (betaE-ACTH)/betaE dysregulation index were unrelated to abnormal behavior. None of the POMC products differed significantly by subjects' species, age, or weight. The finding that intact beta-endorphin is positively related to abnormal behavior in two species of macaque is consistent with some previous research on human subjects and nonprimates. The positive relation of the N-terminal fragment of betaE to abnormal behavior is a new finding.
Crockett
Carolyn M
CM
National Primate Research Center, Box 357330, University of Washington, Seattle, WA 98195-7330, USA. crockett@u.washington.edu
Sackett
Gene P
GP
Sandman
Curt A
CA
Chicz-DeMet
Aleksandra
A
Bentson
Kathleen L
KL
D000818:Animals; D001522:Behavior, Animal; D005260:Female; D008252:Macaca fascicularis; D008254:Macaca nemestrina; D008297:Male; D013045:Species Specificity; D001615:beta-Endorphin / Q000097:blood*
D001615:beta-Endorphin
Am J Ment Retard. 1990 Jul;95(1):93-102
2167107
Am J Primatol. 2002 Oct;58(2):57-69
12386914
Endocr Rev. 1988 Feb;9(1):159-79
3286233
Peptides. 2000 Jun;21(6):785-91
10958998
Psychosom Med. 1993 Jan-Feb;55(1):23-8
8383349
Front Biosci. 2005 Jan 1;10:1-11
15576335
Contemp Top Lab Anim Sci. 1997 Nov;36(6):53-60
16450978
Neurosci Biobehav Rev. 2004 Jan;27(8):777-86
15019427
DNA. 1988 Nov;7(9):627-35
3229286
J Neurosci Res. 1995 Oct 1;42(2):228-35
8568923
Psychoneuroendocrinology. 2004 Nov;29(10):1300-8
15288709
Mol Psychiatry. 2004 Jan;9(1):99-108
14699447
Psychoneuroendocrinology. 2000 Jan;25(1):1-35
10633533
Comp Med. 2005 Aug;55(4):387-92
16158915
Experientia. 1986 Feb 15;42(2):198-9
3948975
Ann N Y Acad Sci. 1999 Oct 20;885:1-21
10816638
Am J Primatol. 1993;30(1):55-74
31941178
Peptides. 2005 Apr;26(4):701-5
15752586
Peptides. 1989 May-Jun;10(3):565-9
2528726
Neurosci Biobehav Rev. 1998 May;22(3):437-52
9579331
Res Dev Disabil. 2005 Nov-Dec;26(6):527-47
15885981
Biol Psychiatry. 1999 Jan 15;45(2):158-63
9951562
Annu Rev Psychol. 1982;33:87-101
6277239
Am J Ment Retard. 1990 Jul;95(1):84-92
2167106
J Med Primatol. 2003 Jun;32(3):148-60
12823625
J Psychosom Res. 2002 Oct;53(4):865-71
12377295
J Autism Dev Disord. 2003 Aug;33(4):443-8
12959423
Res Dev Disabil. 2005 Nov-Dec;26(6):548-64
16303583
Am J Primatol. 1991;25(2):115-124
31948185
Physiol Behav. 2003 Jan;78(1):33-9
12536008
Psychoneuroendocrinology. 2000 Nov;25(8):799-817
10996475
J Anim Sci. 1986 Jun;62(6):1776-86
3525490
Neurotoxicol Teratol. 1996 Sep-Oct;18(5):539-46
8888018
Psychiatry Res. 1995 Oct 16;58(3):191-201
8570775
Am J Primatol. 1998;44(1):29-41
9444321
Am J Psychiatry. 2000 Aug;157(8):1252-9
10910787
Am J Ment Retard. 2000 Mar;105(2):103-17
10755174
Peptides. 1988 Mar-Apr;9(2):325-31
2836825
ILAR J. 2005;46(2):106-17
15775020
Regul Pept. 2002 Oct 15;108(2-3):179-85
12220743
Am J Primatol. 2003 Jan;59(1):3-19
12526035
Am J Psychiatry. 1994 Dec;151(12):1797-801
7977888
Vet Dermatol. 2004 Dec;15(6):389-91
15585015