Glucocorticoid synthesis is a complex, multistep process that starts with cholesterol being delivered to the inner membrane of mitochondria by StAR and StAR-related proteins.
The pregnenolone-progesterone-allopregnanolone pathway is receiving increasing attention in research on the role of neurosteroids in pathophysiology, particularly in stress-related and drug use disorders. These disorders involve an allostatic change that may result from deficiencies in allostasis or adaptive responses, and may be downregulated by adjustments in neurotransmission by neurosteroids.
Considerable evidence from preclinical and clinical studies shows that steroids and in particular neurosteroids are important endogenous modulators of several brain-related functions.