Difference between plasma N- and C-terminally directed beta-endorphin immunoreactivity in infantile autism.
OBJECTIVE
The authors investigated whether there is excessive opioid activity in infantile autism by measuring plasma beta-endorphin in patients with autism compared with patients who had Rett's syndrome and normal comparison subjects.


METHODS
Radioimmunoassays for beta-endorphin using C-terminally and N-terminally directed antisera were applied to plasma samples from 67 children who met both DSM-III-R and ICD-10 diagnostic criteria for infantile autism, 22 girls with Rett's syndrome, and 67 normal children matched in age and sex with the children with autism.


RESULTS
Median N-terminally directed beta-endorphin immunoreactivity appeared to be slightly lower in subjects with autism (7 pg/ml) and clearly higher in the girls with Rett's syndrome (40 pg/ml) than in the comparison subjects (9 pg/ml). Median C-terminally directed beta-endorphin immunoreactivity was higher in the girls with Rett's syndrome (35 pg/ml) and much higher in patients with autism (70 pg/ml) than in comparison subjects (8 pg/ml).


CONCLUSIONS
These findings demonstrate the existence of a wide discrepancy between C- and N-terminally directed beta-endorphin immunoreactivity among children with autism. Despite the fact that the nature of the antigen recognized in the plasma of autistic children by the C-terminally directed anti-beta-endorphin serum remains to be characterized, the difference between C- and N-terminally directed beta-endorphin immunoreactivity might suggest an abnormal processing of the pro-opiomelanocortin gene in infantile autism.
Leboyer
M
M
Hôpital Robert Debré, Université de Paris VII, France.
Bouvard
M P
MP
Recasens
C
C
Philippe
A
A
Guilloud-Bataille
M
M
Bondoux
D
D
Tabuteau
F
F
Dugas
M
M
Panksepp
J
J
Launay
J M
JM
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D001321:Autistic Disorder / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D004298:Dopamine / Q000097:blood; D004399:Dynorphins / Q000097:blood; D004743:Enkephalin, Leucine / Q000097:blood; D004744:Enkephalin, Methionine / Q000097:blood; D004837:Epinephrine / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000097:blood; D018847:Opioid Peptides / Q000097:blood; D010454:Peptide Termination Factors; D011333:Pro-Opiomelanocortin / Q000235:genetics / Q000378:metabolism; D011863:Radioimmunoassay; D015518:Rett Syndrome / Q000097:blood; D001615:beta-Endorphin / Q000096:biosynthesis / Q000097:blood* / Q000235:genetics
D018847:Opioid Peptides; D010454:Peptide Termination Factors; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D001615:beta-Endorphin; D011333:Pro-Opiomelanocortin; D004399:Dynorphins; D000324:Adrenocorticotropic Hormone; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine