3313 12 Project Groups - 2008

PLEASE NOTE: you are scheduled to meet with your project consultant in WEEK 2 – during Tutorial 1 (Monday or Wednesday). If you cannot ALL come at this time, please organise ANOTHER time now instead PLEASE NOTE: you are scheduled to meet with your project consultant in WEEK 2 – during Tutorial 1 (Monday or Wednesday). If you cannot ALL come at this time, please organise ANOTHER time now instead with your consultant for you ALL to meet TOGETHER next week Aim: Measure concentrations of total and biologically free cortisol in human blood and saliva. Rationale A stress response by the human body in reaction to a threat or challenge is mediated by the hypothalamic-pituitary-adrenal (HPA) axis. This axis represents a cascade of biological events that results in cortisol release into the blood circulation to act via corticosteroid receptors in peripheral organs and the brain and underpin a physiological reaction to stress. Measures of cortisol levels in the blood can be indicative of how well an individual reacts to a specific stress stimulus (measures of stress-induced HPA activity) or in general how well an individual copes with stress and changes in the environment over time (measure of basal HPA activity). In the Raine Study of Western Australia, we have been able to follow a cohort of several thousand babies from in utero to late adolescence. In this cohort study data on early life events, which can influence the basal level of HPA activity later in life, will be associated with levels of cortisol in their late teens to study how the level of HPA activity can affect maturation of brain function needed to grow from a teenager into a healthy young adult. We have so far used a radioimmunoassay to measure cortisol in the many samples we already have collected in the Raine Study 16-year follow up. An alternative would be to use an ELISA to measure cortisol in plasma and saliva, sometimes with a higher sensitivity. To evaluate the accuracy of our preliminary data in the human study, we would like to undertake a comparative analysis of RIA vs ELISA outcomes in selected samples from individuals with a hypo-responsive HPA axis, normal HPA axis and hyper-responsive HPA axis. Tissue: Fasting morning plasma and awakening saliva collected from 16 year old teenagers in the Raine Study. Techniques: Enzyme-Linked ImmunoSorbent Assay(ELISA) hormone analysis using 96 well plate systems Analysis: Comparative analysis …