Two Chronic Stress Models Based on Movement Restriction in Rats Respond Selectively to Antidepressant Drugs: Aldolase C As a Potential Biomarker.

Background: Clinically depressed individuals respond to different types of antidepressants, suggesting that different neurobiological mechanisms may be responsible for their depression. However, animal models to characterize this are not yet available.

Methods: We induced depressive-like behaviors in rats using 2 different chronic stress models: restraint in small cages or immobilization in adaptable plastic cones.

The glycolytic enzyme aldolase C is up-regulated in rat forebrain microsomes and in the cerebrospinal fluid after repetitive fluoxetine treatment.

The antidepressant drug fluoxetine is widely used for the treatment of a broad range of psychiatric disorders. Its mechanism of action is thought to involve cellular adaptations that are induced with a slow time course after initiation of treatment. To gain insight into the signaling pathways underlying such changes, the expression levels of proteins in a microsomal sub-fraction enriched in intracellular membranes from the rat forebrain was analyzed after two weeks of treatment with fluoxetine.

Augmentation of the behavioural effects of desipramine by repeated immobilization stress.

The present report provides evidence that repeated immobilization stress (RIS) induced a noradrenergic-dependent depressive-like behaviour and an augmented behavioural response to desipramine (DMI), a noradrenaline reuptake inhibitor (NRI), in the forced swimming test (FST). The present results show that RIS decreased the baseline of climbing behaviour in the FST. Whereas subchronic administration of DMI (10mg/kg, three times in a 24h period) induced a significantly higher increase in climbing behaviour on repeatedly stressed rats compared to controls.

Desipramine prevents the sustained increase in corticotropin-releasing hormone-like immunoreactivity induced by repeated immobilization stress in the rat central extended amygdala.

Clinical and experimental studies have shown that the activation of corticotropin-releasing hormone (CRH) and noradrenergic systems mediate stress-induced anxiety. Repeated immobilization stress (RIS) has been shown to induce long-lasting anxiety behavior and changes in noradrenaline turnover. The present work was aimed at studying the effect of RIS on the in situ expression of CRH-LI in the central extended amygdala and paraventricular nucleus of the hypothalamus (PVN).

Expression of scavenger receptors in glial cells. Comparing the adhesion of astrocytes and microglia from neonatal rats to surface-bound beta-amyloid.

Astrocytes and microglia associate to amyloid plaques, a pathological hallmark of Alzheimer disease. Microglia are activated by and can phagocytose beta-amyloid (Abeta). Scavenger receptors (SRs) are among the receptors mediating the uptake of fibrillar Abeta in vitro.

Adrenalectomy decreases corticotropin-releasing hormone gene expression and increases noradrenaline and dopamine extracellular levels in the rat lateral bed nucleus of the stria terminalis.

The bed nucleus of the stria terminalis (BNST) has a high density of corticotropin-releasing hormone (CRH)-containing neurons that are significantly innervated by noradrenergic and dopaminergic nerve terminals. This limbic structure is involved in the extrahypothalamic response to stress. The purpose of the present work is to study whether the absence of glucocorticoids, induced by a long-term adrenalectomy, regulates CRH gene expression and noradrenaline and dopamine extracellular levels in the rat BNST.