beta-endorphin and Intellectual-Disability

Self-injuring behavior (SIB) is a life-threatening behavior exhibited by many species, including humans, and has no known cause and no agreed upon treatment. The role of the stress axis in the maintenance of this mysterious behavior was examined in subjects with life-long SIB. Over a 6-year period, 40 hr of direct observations of behavior and the environment were recorded on palmtop computers while 36 residential subjects (28 target and 8 control subjects) conducted their daily activities. Blood samples were collected in morning and evening for all subjects and within minutes after a self-injuring act in 28 target subjects who exhibited SIB to determine levels of ACTH and B-endorphin (BE). Self-injuring events in the patient group were significantly sequentially dependent (i.e., the only predictor of a self-injuring act was an antecedent self-injuring act). Higher morning levels of BE relative to ACTH predicted [r(df=27) = .57, p < .001] the sequentially dependent pattern of SIB. This effect was validated in a subgroup retested several months later [r(df=22) = .60, p < .001]. A subgroup of seven subjects exhibiting sequentially dependent patterns were administered an opiate blocker (naltrexone) in a double-blind, crossover design with an additional 14 hr/week of observation for 7 weeks. Naltrexone challenge interrupted the sequential pattern (improved behavior) in subjects with elevated BE immediately following SIB (r = .85, p < .01). The pattern of results supported the conclusion that the stress axis played a significant role in the maintenance of complex episodes of self-injury.

Topics: Adrenocorticotropic Hormone; Adult; Arousal; beta-Endorphin; Circadian Rhythm; Computers, Handheld; Cross-Over Studies; Dose-Response Relationship, Drug; Double-Blind Method; Female; Follow-Up Studies; Humans; Intellectual Disability; Male; Middle Aged; Naltrexone; Narcotic Antagonists; Pro-Opiomelanocortin; Reference Values; Self-Injurious Behavior; Social Environment

Plasma levels of the hypothalamo-pituitary-adrenal axis hormones beta-endorphin (BE), adrenocorticotropin hormone (ACTH), and cortisol were measured in autistic (N = 48), mentally retarded/cognitively impaired (MR/CI, N = 16), and normal control (N = 26) individuals. Comparison of log transformed data from the three groups revealed that levels of BE and ACTH were significantly higher (p < .05) in the autistic individuals than in normal controls. The higher means in the autistic group were due to significantly higher plasma levels of BE and ACTH, indices of acute stress response, in the more severely affected individuals. The data support the idea that individuals with severe autism have a heightened response to acute stressors rather than chronic hyperarousal or elevated basal stress response system functioning.

Topics: Adolescent; Adrenocorticotropic Hormone; Arousal; Autistic Disorder; beta-Endorphin; Child; Female; Humans; Hydrocortisone; Hypothalamo-Hypophyseal System; Intellectual Disability; Intelligence; Male; Pituitary-Adrenal System; Reference Values

It has been suggested that the key variable in reduced plasma immunoreactive beta-endorphin concentrations in autistic subjects may be concomitant self-injurious behaviour.. We studied morning levels of plasma beta-endorphin in 33 learning disabled people with self-injurious and/or autistic behaviour.. The beta-endorphin level of the subjects with severe self-injurious behaviour proved to be significantly lower than of autistic subjects without severe self-injurious behaviour (3.6 (1.4) pmol/l v. 5.8 (4.3) pmol/l; t-test: P = 0.045. Replication: 3.7 (1.1) pmol/l v. 5.7 (3.8) pmol/l; t-test: P = 0.043). Individuals with mild and occasional self-injurious behaviour were found to have beta-endorphin levels comparable to those without self-injurious behaviour. Further, subjects being treated with neuroleptics and lower beta-endorphin levels than untreated subjects.. These results stress that in any study of opioid systems of learning disabled people, it is very important to differentiate between people with and without severe self-injurious behaviour. The results support the idea that severe self-injurious behaviour may be related to functional disturbances in the endogenous opioid system.

Topics: Adult; Autistic Disorder; beta-Endorphin; Brain; Female; Humans; Intellectual Disability; Learning Disabilities; Male; Psychiatric Status Rating Scales; Receptors, Opioid; Self-Injurious Behavior

There are no reports of an association between the menstrual cycle and self-injurious behavior (SIB) in the mentally retarded population. However, the endogenous opiate system has been implicated in both menstrual cycling and SIB. Catamenial and behavioral records of 9 women with mental retardation who exhibited SIB were analyzed for 6 months to determine the association between phases of the menstrual cycle and rates of SIB. Menstrual cycles were divided into four phases: (a) menses and early follicular phase, (b) late follicular phase, (c) early luteal phase, and (d) late luteal or premenstrual phase. Analysis showed that the highest frequency of SIB occurred in the first two phases: 43.5% during early follicular phase and 47.3% in the late follicular phase. Pairwise t and binomial expansion tests confirmed that SIB was cyclic across the menstrual cycle with Phase 1 > Phase 3, Phase 1 > Phase 4, Phase 2 > Phase 3, and Phase 2 > Phase 4. Seven of the 9 women were cyclers and manifested identical phase/SIB relations. The cyclical character of SIB may relate to changing peripheral and central endorphin and pain threshold during the cycle.

Topics: Adolescent; Adult; beta-Endorphin; Female; Follicular Phase; Humans; Intellectual Disability; Menstrual Cycle; Self-Injurious Behavior; Women's Health

Topics: Adult; Autistic Disorder; beta-Endorphin; Humans; Hydrocortisone; Immunoradiometric Assay; Intellectual Disability

Topics: Autistic Disorder; beta-Endorphin; Blood Pressure; Female; Fetal Blood; Fetal Hypoxia; Humans; Hydrocortisone; Hypoxanthine; Hypoxanthines; Intellectual Disability; Multivariate Analysis; Pregnancy; Self Mutilation; Stereotyped Behavior; Stress, Physiological

B-endorphin and cortisol concentrations were examined in the plasma of mentally retarded patients who displayed symptoms of self-injurious behavior (SIB) (n = 9), stereotypy (n = 17), or SIB plus stereotypy (n = 14). Morning and evening samples were compared with a matched patient control group (n = 13) and a group of nonretarded controls (n = 17). Compared with nonretarded controls, the retarded control group had significantly lower b-endorphin concentrations for the morning sample and nonsignificantly lower concentrations for the evening sample. The combined patient groups had lower b-endorphin levels than did nonretarded controls for both samples. Patients with SIB and stereotypy had significantly higher morning levels of b-endorphin than the retarded controls. The evening levels of the SIB plus stereotypy group also were higher than retarded controls but were not significant. Levels in the SIB and stereotypy group were slightly elevated compared with retarded controls. Cortisol levels were identical for all groups. B-endorphin and cortisol significantly covaried for the nonretarded controls but not the patients. Results indicated that compared to a matched control group, patients with SIB plus stereotypy have elevated b-endorphin plasma.

Topics: Adult; Arousal; beta-Endorphin; Female; Humans; Hydrocortisone; Intellectual Disability; Male; Receptors, Opioid; Self Mutilation; Stereotyped Behavior

Plasma levels of beta-endorphin (beta-EP) and prolactin (PRL) were measured in 5 girls with Rett syndrome and in a control group before and after giving 10 mg metoclopramide i.v. beta-lipotropin (beta-LPH) was only measured in basal conditions. Basal values of beta-EP and beta-LPH were lower than in control individuals. The responses of plasma beta-EP to metoclopramide in Rett syndrome patients were less intense than in control individuals, while the PRL increase in girls with Rett syndrome was significantly higher than in control subjects. These preliminary data suggest a derangement of the dopaminergic system.

Topics: Adolescent; beta-Endorphin; beta-Lipotropin; Child; Child, Preschool; Endorphins; Female; Humans; Intellectual Disability; Metoclopramide; Movement Disorders; Prolactin; Syndrome

The relationships among "paradoxical" excitement to sedative--hypnotic medication, self-injurious behavior, and perinatal trauma were evaluated. Mentally retarded patients were classified as either paradoxical or normal responders to sedative-hypnotics. Paradoxical responders to these medications have a lower MA, a history of perinatal trauma, self-injurious behavior (SIB), and aggressive behavior when compared to normal responders. These findings confirmed and extended previous reports that a type of SIB may be indexed by paradoxical response to sedative-hypnotics. Results also suggested that perinatal trauma may be of etiological importance in the development of SIB. Because perinatal trauma or fetal distress results in excessive levels of B-endorphin, in utero, an impaired endogenous opiate system may be a critical factor maintaining a syndrome of SIB. Thus, these data may indicate psychopharmacological markers of SIB that may have both treatment and etiological significance.

Topics: Adolescent; Adult; beta-Endorphin; Endorphins; Female; Humans; Hypnotics and Sedatives; Intellectual Disability; Male; Middle Aged; Pregnancy; Pregnancy Complications; Receptors, Opioid; Self Mutilation; Stereotyped Behavior