[Sensitive to change: neuroendocrinologic aspects of depression in women]. / Gevoelig voor verandering Neuro-endocrinologische aspecten van depressie bij vrouwen.

BACKGROUND: Depression is more prevalent among women than among men. There are several possible explanations for this. There are indications that the aetiology of this difference in prevalence has to do with fluctuations in the oestrogen level, which are a feature of the female reproductive system. The influence of oestrogens on the hypothalamic-pituitary-adrenal axis may play an important role. AIM: To cast light on the deregulating influence of oestrogen on the hypothalamic-pituitary-adrenal axis. This deregulation could lead to depression in a subgroup of women with a neuroendocrine stress response that is sensitive to hormonal fluctuations. METHOD: PubMed was used to review the literature on the basis of the key words 'depression', 'estrogen', 'gender', 'gonadal hormones', 'hpa axis', 'stress' and 'women'. RESULTS: Deregulation of the hypothalamic-pituitary-adrenal axis plays a role in the aetiology of major depression. On the one hand, oestrogens stimulate the activity of this system. On the other hand, a lowering of the endogenous oestrogen level seems to be accompanied by reduced activity of the hypothalamic-pituitary-adrenal axis. CONCLUSION: Changing oestrogen levels characterise the female reproductive system. It is these changing levels--not the absolute oestrogen level--which have the potential to deregulate the hypothalamic-pituitary-adrenal axis.

Prenatal stress and neonatal rat brain development.

Chronic or repeated stress during human fetal brain development has been associated with various learning, behavioral, and/or mood disorders, including depression in later life. The mechanisms accounting for these effects of prenatal stress are not fully understood. The aim of this study was to investigate the effects of prenatal stress on early postnatal brain development, a disturbance of which may contribute to this increased vulnerability to psychopathology. We studied the effects of prenatal stress on fetal growth, stress-induced corticosterone secretion, brain cell proliferation, caspase-3-like activity and brain-derived neurotrophic factor protein content in newborn Fischer 344 rats. In addition to a slight reduction in birth weight, prenatal stress was associated with elevated corticosterone levels (33.8%) after 1 h of maternal deprivation on postnatal day 1, whereas by postnatal day 8 this pattern was reversed (-46.5%). Further, prenatal stress resulted in an approximately 50% decrease in brain cell proliferation just after birth in both genders with a concomitant increase in caspase-3-like activity within the hippocampus at postnatal day 1 (36.1%) and at postnatal day 5 (females only; 20.1%). Finally, brain-derived neurotrophic factor protein content was reduced in both the olfactory bulbs (-24.6%) and hippocampus (-28.2%) of prenatally stressed male offspring at postnatal days 1 and 5, respectively. These detrimental central changes observed may partly explain the increased susceptibility of prenatally stressed subjects to mood disorders including depression in later life.