Effects of Acute Stress or Centrally Injected Interleukin-1beta on Neuropeptide Expression in the Immune System

Acute stress stimulates the expression and release of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) from the hypothalamus, and the pro-opiomelanocortin products beta-endorphin and ACTH from the anterior pituitary. These neuropeptides are also expressed in immune tissues, and it has been proposed that they may modulate immune responses to stress through paracrine mechanisms. We subjected rats to restraint stress or central injection of interleukin (IL)-1beta to determine whether these acute stimuli can alter the expression of neuropeptides in the spleen and thymus. Restraint stress significantly increased the contents of all these neuropeptides in thymic, but not splenic, extracts. A single icv injection of IL-1beta increased contents of CRH, AVP, ACTH and beta-endorphin in the spleens of both sham-operated and adrenalectomised (ADX) rats. IL-1beta increased thymic contents of CRH and ACTH in sham-operated rats but these increases were not observed in ADX rats. These results suggest that the effects of IL-1beta on neuropeptide expression in the spleen are independent of glucocorticoids, whereas IL-1beta stimulation of neuropeptide expression in the thymus is dependent on circulating glucocorticoids. There were significant correlations between increases in CRH, ACTH and beta-endorphin in the spleen, and between CRH and ACTH in the thymus, consistent with the suggestion that IL-1beta-induced increases in ACTH and beta-endorphin may be mediated through CRH. These results provide evidence that stressors can directly influence neuropeptide expression in immune tissues. Thus stress may influence immune functions through paracrine mechanisms involving locally synthesised neuropeptides as well as through activation of the hypothalamo-pituitary-adrenal axis.     

Characteristics and consequences of help-giving practices in contrasting human services programs

Relationships between human services program models and help-giving practices, and between both program models and help-giving practices and help-seeker control appraisals were examined in a study of 107 low socioeconomic background families. Three kinds of human services agencies were included in the study, each of which differed in terms of their implicit and explicit assumptions about the families they served and the roles professionals and families played as part of helping relationships. Results support the hypotheses that (a) a program philosophy that was family centered would be associated with more empowering help-giving practices compared to more professionally centered philosophies and (b) a family-centered program philosophy and empowering help-giving practices would be related to an enhanced sense of personal control over needed supports and resources from a target help-giver.     

Hypothalamo-Pituitary-Adrenocortical Regulation Following Lesions of the Central Nucleus of the Amygdala

Previous reports indicate that the central nucleus of the amygdala (CeA) stimulates adrenocorticotropin and corticosterone secretion, suggesting a role for this region in central hypothalamo-pituitary-adrenocortical (HPA) stress regulation. To evaluate this hypothesis, this study assessed the impact of CeA lesion on the response of hypophysiotrophic paraventricular nucleus (PVN) neurons to acute restraint and chronic unpredictable stress exposure. In contrast to previous reports, CeA lesions did not affect corticosterone or ACTH secretion induced by acute stress. Acute restraint increased PVN corticotropin releasing hormone (CRH) mRNA expression, increased the number of parvocellular PVN neurons expressing the co-secretagogue arginine vasopressin (AVP), and induced cFOS mRNA expression in the parvocellular PVN. However, there was no additional effect of CeA lesion on any measure of PVN activation. Chronic unpredictable stress exposure induced long-term activation of the HPA axis, noted by thymic involution, adrenal hypertrophy and increased PVN CRH mRNA expression. Stress-induced changes in thymus and adrenal weights were not affected by CeA lesion. Further, CeA lesion rats did not differ from controls in post-stress CRH mRNA expression. However, basal CRH mRNA expression was increased in the PVN of CeA rats, suggesting that the CeA plays a role in long-term inhibition of the PVN. The results of these studies are not consistent with the hypothesis that the CeA is necessary for stress-induced pituitary-adrenocortical activation. Rather, this region may play a stressor-specific modulatory role in regulation of HPA function.     

Looking beyond the parent-child dyad for the determinants of maternal styles of interaction

The manner in which maternal, family, and child characteristics; personal well-being and health; intrafamily functioning and support; and several dimensions of informal support were related to five different maternal styles of interaction was examined. The subjects were 102 mothers of retarded, handicapped, and developmentally at-risk young children. The mothers completed several self-report measures of well-being and support, were interviewed about their personal social networks, and were observed interacting with their child in a free-play episode. Canonical correlation analysis showed that there were multiple determinants of interactive styles, although there was considerable specificity with respect to the particular variables that were related to the five interactive styles. Social support was related significantly to four of the maternal interactive styles, which indicates that the parenting behavior was influenced in part by factors other than the individual characteristics of the dyad members.     

Meta-analysis of family-centered helpgiving practices research

A meta-analysis of 47 studies investigating the relationship between family-centered helpgiving practices and parent, family, and child behavior and functioning is reported. The studies included more than 11,000 participants from seven different countries. Data analysis was guided by a practice-based theory of family-centered helpgiving that hypothesized direct effects of relational and participatory helpgiving practices on self-efficacy beliefs and parent, family, and child outcomes. Results showed that the largest majority of outcomes were related to helpgiving practices with the strongest influences on outcomes most proximal and contextual to help giver/help receiver exchanges. Findings are placed in the context of a broader-based social systems framework of early childhood intervention and family support.     

Young children's natural learning environments: contrasting approaches to early childhood intervention indicate differential learning opportunities

1,000 parents of infants and toddlers enrolled in early childhood intervention programs were surveyed about the number of learning opportunities provided their preschool children using different approaches to early intervention. Findings showed that more learning opportunities were reported when participation in everyday activity settings was conceptualized as a type of intervention rather than as settings for professionals to conduct their interventions.     

Influence of the interests of children with autism on everyday learning opportunities

Findings from a pilot study investigating the influence of the interests of young children with autism on parents' provision of everyday informal child learning opportunities are described. 17 children (13 boys, 4 girls) were divided into two groups that received everyday learning opportunities of Low interest and High interest, based on parents' bi-weekly ratings of the interestingness of the opportunities to the children, using an investigator-developed measure. A brief intervention of 12 to 14 weeks showed that the children in the High interest-based group were provided more learning opportunities than were the Low interest-based group, and that the parents indicated that their children benefited more from the learning opportunities. Implications for future research are described.