Correlation between Changes in Stress-Induced Corticosterone Secretion and GR mRNA Levels

The current study was conducted to determine the potential relationship between stress-induced corticosterone secretion and corticosteroid receptor mRNA levels after 5 days of intermittent stress. In particular, we were interested in the rate at which animals terminate a stress response, and how this termination may be altered by repeated stress. Adult male Sprague-Dawley rats were subjected to either 5 days of restraint stress or 5 days of an unpredictable stress paradigm. Restraint-stress induced corticosterone secretion was measured on Days 1 and 5 in both groups, and animals were killed on Day 6. Glucocorticoid receptor (GR), and mineralocorticoid (MR) mRNA levels were determined using in-situ hybridization techniques. Five days of restraint stress caused an habituation of the plasma corticosterone response to stress measured 60 and 90 min post-stress initiation; this pattern of corticosterone secretion was not observed in the animals subjected to unpredictable stress. Five days of either stress paradigm did not alter MR mRNA levels measured within the hippocampus or GR mRNA levels within the hippocampus or the medial parvocellular division of the paraventricular nucleus of the hypothalamus (mpPVN). However, an individual's GR mRNA levels measured within the CA1/2 region of the hippocampus and the mpPVN were significantly correlated with the degree of habituation of the corticosterone response to stress measured on Day 5. This suggests that an increase in the rate of termination of the stress response and levels of GR within the hippocampus and mpPVN may be functionally related.     

Online access by adolescents in Accra: Ghanaian teens' use of the internet for health information

In developed countries, adolescents go online to find information about health; however, little is known about the online practices of youth from developing countries. This study's purpose was to explore and provide current information, drawn from adolescents living in Ghana's capital city of Accra, on the use of the Internet as a health information source. Using a representative sample of in-school adolescents and a convenience sample of out-of-school adolescents, 778 15- to 18-year-olds completed a detailed media and health information survey. Two-thirds (66%) of the in-school youth and approximately half (54%) of the out-of-school youth had previously gone online. Of all these Internet users, 53% had sought online health information, and this percentage did not differ significantly by gender, age, ethnicity, or even school status. Youth reported great interest, high levels of efficacy, and positive perceptions of online health information. Although more research should be conducted, this study offers exciting data on the potential to deliver, via the Internet, health information to youth in developing countries.