Salivary cortisol and cardiovascular activity during stress in oppositional-defiant disorder boys and normal controls

Background: Arousal-regulating mechanisms are important in explaining individual differences in antisocial behavior. Methods: Alterations in salivary cortisol concentration and cardiovascular activity were studied in 21 boys with oppositional defiant disorder (ODD) and 31 normal controls (NC) during a 2-hour stressful procedure involving frustration and provocation. Results: Baseline levels of heart rate (HR) were significantly lower in the ODD group, but their HR levels were higher during provocation and frustration. Cortisol levels in the ODD group were overall lower than those of the NC group, and the effect of stress seemed to be minimal and similar for both groups; however, individual differences were large. Since anxiety plays an important mediating role in cortisol response, subjects were divided into one of four groups based on the intensity of their externalizing behavior and anxiousness. Cortisol increase due to stress exposure was strongest in highly externalizing and highly anxious subjects; cortisol decrease was strongest in those subjects who were high in externalizing behavior and low in anxiousness. Conclusions: The results of the study support an important role for hypothalamic-pituitary-adrenal axis sympathetic autonomic functioning in persistent antisocial behavior in young boys

Autonomic and neuroendocrine responses to a psychosocial stressor in adults with autistic spectrum disorder

Objective of the study was to replicate in adults our previous findings of decreased heart rate and normal endocrine responses to stress in autistic children and to elucidate the discrepancy between autonomic and endocrine stress responses by including epinephrine, norepinephrine, oxytocin and vasopressin measurements. Ten autistic spectrum disorder (ASD) adults were compared to 14 healthy controls in their response to a psychosocial stressor (public speaking). ASD patients showed decreased heart rate, but normal cortisol responses, consistent with our prior findings in children. No differences in norepinephrine, epinephrine, oxytocin or vasopressin responses to stress were found. However, in contrast to previous findings in low functioning autistic children, ASD adults showed increased basal oxytocin levels, which may be related to developmental factors

Isolation and characterization of α-endorphin and γ-endorphin from single human pituitary glands

Abstractα-endorphin and γ-endorphin, two closely related peptides of the pro-opiomelanocortin family with characteristics biological activities, were purified to homogeneity from single human pituitary glands and chemically identified. Isolation of the peptides was based on size fractionation by Sephadex G-75 chromatography followed by two HPLC steps using reverse-phase and paired-ion reverse-phase systems and was monitored by radioimmunoassay. During the isolation procedure α-and γ-endorphin-sized material behaved chromatographically and immunologically indistinguishably from synthetic α- and γ- endorphin. The amino acid composition and NH2-terminus of isolated peptides demonstrated their identity as authentic α-endorphin and γ-endorphin. Acetylated forms were absent. In addition, evidence is provided that large forms with α- and γ-endorphin immunoreactivity detected during gel filtration are human lipotropin-(1–74) and -(1–75), respectively. The data substantiate that α-endorphin and γ-endorphin exist as endogenous peptides in the human pituitary gland