(no subject)
Allopregnanolone is an endogenous steroid hormone which is a positive allosteric modulator of GABA-A channels in the brain. It is one of many so-called neuroactive steroids which interact with membrane-bound ligand-gated ion channels. This is in contrast with classic steroids which are thought to only bind to cytoplasmic receptors mediating gene expression.
- GABA-A receptors bind numerous ligands: benzodiazepines, GABA, ethanol, imidazopyridines and barbiturates.
- Most of these ligands are allosteric modulators and may therefore have a greater effect when given in combination (downers and booze are a common example).
- Allopregnanolone can reduce anxiety and depression-like symptoms in rodent models
- Allopregnanolone is increased in the brain during and after exposure to stressful situations and may function as an endogenous benzodiazepine.
- Allopregnanolone may also have a role in the regulation of mood, especially in pregnant or menstruating women.