Early life stress alters adult serotonin 2C receptor pre-mRNA editing and expression of the alpha subunit of the heterotrimeric G-protein G q

Infant maternal separation, a paradigm of early life stress in rodents, elicits long-lasting changes in gene expression that persist into adulthood. In BALB/c mice, an inbred strain with spontaneously elevated anxiety and stress reactivity, infant maternal separation led to increased depression-like behavioral responses to adult stress and robustly increased editing of serotonin 2C receptor pre-mRNA. Chronic fluoxetine treatment of adult BALB/c mice exposed to early life stress affected neither their behavioral responses to stress nor their basal 5-HT2C pre-mRNA editing phenotype. However, when fluoxetine was administered during adolescence, depression-like behavioral responses to stress were significantly diminished in these mice, and their basal and stress-induced 5-HT2C pre-mRNA editing phenotypes were significantly lower. Moreover, when BALB/c mice exposed to early life stress were raised in an enriched postweaning environment, their depression-like behavioral responses to adult stress were also significantly diminished. However, their 5-HT2C pre-mRNA editing phenotype remained unaltered. Hence, the similar behavioral effects of enrichment and fluoxetine treatment during adolescence were not accompanied by similar changes in 5-HT2C pre-mRNA editing. Enriched and nonenriched BALB/c mice exposed to early life stress also exhibited significantly increased expression of mRNA and protein encoding the G alpha q subunit of G-protein that couples to 5-HT2A/2C receptors. In contrast, G alpha q expression levels were significantly lower in fluoxetine-treated mice. These findings suggest that compensatory changes in G alpha q expression occur in mice with persistently altered 5-HT2C pre-mRNA editing and provide an explanation for the dissociation between 5-HT2C receptor editing phenotypes and behavioral stress responses.

Ethical considerations in health care benefits administration

Defining the scope of coverage and limitations in various health plans has become an increasingly difficult and confusing issue. The historical shift to managed care has fundamentally altered the limitations on health care benefits. Because of the existence of "benefits exclusions," confusing issues have emerged in managed care situations. Fundamental fear of health care rationing has raised the awareness of the general public to the ethics of this issue. This article discusses the definitions and examples of certain types of health benefit exclusions and the ethical considerations related to such exclusions.

Cultivation of mycoplasmas in a modified tissue culture medium

A new medium, which contained a chemically defined tissue culture base ("medium 199"), was developed for the cultivation of mycoplasmas. When supplemented with albumin, glucose, serum, and yeast extract, the new medium adequately supported the growth of Mycoplasma and Acholeplasma species.