Prenatal stress alters cytokine levels in a manner that may endanger human pregnancy.

OBJECTIVE: Recent data suggest that prenatal stress negatively affects pregnancy and infant outcome. Existing studies implicate dysregulation of the immune and endocrine systems in stress-related increases in premature labor and poor birth outcome, but no published studies have directly addressed the relationships among these variables during pregnancy. We sought to test the hypothesis that high levels of psychosocial stress and low levels of social support during pregnancy alter maternal cytokine profiles in a manner that contributes to poor birth outcomes. METHODS: Psychosocial stress and social support were measured in 24 women with overtly normal pregnancies once during each trimester of pregnancy. Levels of interleukin-10 (IL-10), IL-6, and tumor necrosis factor-alpha (TNF-alpha) were assessed concurrently with stress and support measurements. RESULTS: High social support was associated with low stress scores. Elevated stress scores were positively correlated with higher levels of the proinflammatory cytokines IL-6 and TNF-alpha, and with low levels of the antiinflammatory cytokine IL-10. CONCLUSIONS: These findings provide initial support for our hypothesis that stress-related neural immune interactions may contribute to pregnancy complications and poor outcome, but require further study to determine the mechanism and significance of these effects.

Lithium alters measures of auditory gating in two strains of mice.

BACKGROUND: There are similarities between schizophrenia and bipolar disorder, especially during the psychotic phase. Auditory gating deficits are common in both schizophrenia (does not remit postpsychotic event) and bipolar disorder (only during the manic phase). Lithium has been used to treat psychosis acutely in both bipolar disorder and schizophrenia. An animal model was used to assess the effects of lithium treatment on normal and deficient auditory gating. METHODS: Mice of the DBA/2 (deficient gating) and C3H (normal gating) strains were treated for 6 weeks with either standard rodent chow or rodent chow supplemented with 2.55g/kg lithium carbonate. After 6 weeks of treatment, auditory evoked potentials were recorded under anesthesia. Differences between the groups and treatments were determined using analysis of variance. RESULTS: The normally impaired DBA/2 mice showed improved auditory gating following lithium treatment, while the C3H mice, the benchmark "normal" mouse strain, were impaired after lithium treatment. CONCLUSIONS: C3H mice treated with lithium had significantly impaired auditory gating as a result of treatment. This may be due to norepinephrine facilitation, through a blockade of presynaptic alpha(2) autoreceptors. DBA/2 mice had improved gating as a result of treatment with lithium, likely due to improved functioning of the gamma-aminobutyric acid system.