The neurosteroid 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone) has been reported to have rewarding properties in mice tested for place conditioning. Another study found that allopregnanolone reduced dopamine (DA) output in the nucleus accumbens (NAc) of rats. As many rewarding stimuli increase accumbens DA, these results may appear contradictory. Thus, the present study examined the r...

We compared the effects of three different doses of allopregnanolone (4, 8 or 16 mg/kg), a metabolite of progesterone, to progesterone (16 mg/kg) in adult rats with controlled cortical impact to the pre-frontal cortex. Injections were given 1 h, 6 h and every day for 5 consecutive days after the injury. One day after injury, both progesterone-treated (16 mg/kg) and allopregnanolone (8 or 16 mg/...

The pineal gland transduces photoperiodic changes to the neuroendocrine system by rhythmic secretion of melatonin. We recently provided new evidence that the pineal gland is a major neurosteroidogenic organ and actively produces a variety of neurosteroids de novo from cholesterol in birds. Notably, allopregnanolone is a major pineal neurosteroid that is far more actively produced in the pineal ...

The neurosteroid 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone) facilitates GABA(A) receptor-mediated ionic currents via allosteric modulation of the GABA(A) receptor. Accordingly, allopregnanolone caused an increase in the slow decay time constant of spontaneous GABA-mediated IPSCs in magnocellular neurons recorded in hypothalamic slices. The allopregnanolone effect on IPSCs was inhib...

AIM To exam the effects of allopregnanolone and gamma-amino-butyric acid (GABA) on the excitotoxicity. METHODS The excitotoxicity was evoked by kainate (KA) in the primary culture of rat cerebral cortical cells. Effect of allopregnanolone or GABA on the excitotoxicity was examined by the measurement of lactate dehydrogenase (LDH) activity released in the culture medium. RESULTS Either acute...

Gamma-aminobutyric acid (GABA)-mediated transmission in the medial preoptic area (MPOA) of the hypothalamus plays an important role in functions such as sex steroid hormone dynamics and control of body temperature. The action of allopregnanolone, the primary metabolite of progesterone, on GABAergic transmission was investigated by employing patch clamp whole cell recording on acutely dissociate...

BACKGROUND Neurosteroids such as allopregnanolone and pregnanolone are suggested to be of importance for the pathophysiology of premenstrual dysphoric disorder. The aim of this study was to investigate whether the luteal-phase serum concentrations of these neurosteroids are associated with improvement of premenstrual symptoms in 12 women with severe premenstrual syndrome after treatment with lo...

STUDY OBJECTIVE We compare the effects of postinjury administration of allopregnanolone, a metabolite of progesterone, to progesterone in an animal model of transient middle cerebral artery occlusion. METHODS Focal cerebral ischemia was induced in age-matched, adult, male, Sprague-Dawley rats by using an intraluminal filament and suture method to occlude the right middle cerebral artery. Afte...

Hyperglycemia plays a critical role in the development of diabetic neuropathy. Hyperglycemia induces oxidative stress in neurons, resulting in neuronal cell apoptosis and dysfunction. Anti-apoptotic properties of neurosteroids have been demonstrated in numerous cellular models of neurodegenerative studies. Here, the protective effects of neurosteroid allopregnanolone were investigated in in vit...

Progesterone, or rather its neuroactive metabolite allopregnanolone, modulates amygdala activity and thereby influences anxiety. Cognition and, in particular, memory are also altered by allopregnanolone. In the present study, we investigated whether allopregnanolone modulates memory for biologically salient stimuli by influencing amygdala activity, which in turn may affect neural processes in o...