The brain 5-HT4 receptor binding is down-regulated in the Flinders Sensitive Line depression model and in response to paroxetine administration.

The 5-hydroxytryptamine (5-HT(4)) receptor may be implicated in depression and is a new potential target for antidepressant treatment. We have investigated the brain 5-HT(4) receptor [(3)H]SB207145 binding in the Flinders Sensitive Line rat depression model by quantitative receptor autoradiography, and related this to 5-HT transporter (S)-[N-methyl-(3)H]citalopram binding. We also determined the regulation of 5-HT(4) receptor binding by 1, 14, and 21 days of paroxetine administration and subchronic 5-HT depletion, and compared this with changes in 5-HT(2A) receptor [(3)H]MDL100907 binding.

Activation of glucocorticoid receptors increases 5-HT2A receptor levels.

Major depression is associated with both dysregulation of the hypothalamic pituitary adrenal axis and serotonergic deficiency, not the least of the 5-HT2A receptor. However, how these phenomena are linked to each other, and whether a low 5-HT2A receptor level is a state or a trait marker of depression is unknown. In mice with altered glucocorticoid receptor (GR) expression we investigated 5-HT2A receptor levels by Western blot and 3H-MDL100907 receptor binding.

Measurements of brain-derived neurotrophic factor: methodological aspects and demographical data.

Although numerous studies have dealt with changes in blood brain-derived neurotrophic factor (BDNF), methodological issues about BDNF measurements have only been incompletely resolved. We validated BDNF ELISA with respect to accuracy, reproducibility and the effect of storage and repeated freezing cycles on BDNF concentrations. Additionally, the effect of demographic characteristics in healthy subjects on BDNF was verified.