Allopregnanolone, a 3α,5α-progesterone metabolite, acts as a potent allosteric modulator of the γ-aminobutyric acid type A receptor. In the present review, the synthesis of this neuroactive steroid occurring in the nervous system is discussed with respect to physiological and pathological conditions. In addition, its physiological and neuroprotective effects are also reported. Interestingly, the levels of this neuroactive steroid, as well as its effects, are sex-dimorphic, suggesting a possible gender medicine based on this neuroactive steroid for neurological disorders. However, allopregnanolone presents low bioavailability and extensive hepatic metabolism, limiting its use as a drug. Therefore, synthetic analogues or a different therapeutic strategy able to increase allopregnanolone levels have been proposed to overcome any pharmacokinetic issues.

中文翻译：

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Allopregnanolone：关于其合成和作用的概述

Allopregnanolone 是一种 3α,5α-孕酮代谢物，可作为 γ-氨基丁酸 A 型受体的有效变构调节剂。在本综述中，就生理和病理条件讨论了在神经系统中发生的这种神经活性类固醇的合成。此外，还报道了其生理和神经保护作用。有趣的是，这种神经活性类固醇的水平及其作用是性别二态的，这表明可能基于这种神经活性类固醇治疗神经系统疾病的性别药物。然而，allopregnanolone 的生物利用度低，肝脏代谢广泛，限制了其作为药物的使用。所以，