What is the Origin of Neurosteroid Signalling?

This concept emerged from the discovery that the brain, glial cells, and peripheral nerves possess the necessary enzymes to synthesize steroids de novo from cholesterol or circulating precursors, giving rise to the term "neurosteroid." The "signalling" emphasizes their role as fast-acting modulators of synaptic transmission, distinct from the slower, genomic effects of classic steroid hormones.

What is the Mechanism of Neurosteroid Signalling?

Neurosteroids primarily exert their rapid, non-genomic effects by directly binding to and modulating the function of ligand-gated ion channels, such as enhancing the inhibitory effect of GABA at the GABA-A receptor. This rapid modulation can quickly alter neuronal excitability and circuit function. Their synthesis is highly sensitive to stress and inflammation, suggesting a local, adaptive mechanism to regulate the neural response to physiological challenges.

Neurosteroid Signalling ∞ Area

Neurosteroid Signalling

Meaning

Neurosteroid Signalling describes the localized synthesis and action of steroid hormones within the central and peripheral nervous systems, where they function as crucial neuromodulators and neuroprotectors, independent of their classical endocrine gland production. These molecules, such as allopregnanolone and DHEA, rapidly influence neuronal excitability, mood, and cognitive function by interacting with neurotransmitter receptors like GABA-A and NMDA receptors. Understanding this signaling pathway is vital for addressing conditions related to stress, anxiety, and neurodegeneration.