Pregnenolone is a hormone made by the adrenal glands, brian, and other organs.
It is made from cholesterol and then used by the body to convert into DHEA,
progesterone, testosterone, estrogen, and other hormones. Supplements of
pregnenolone became available over the counter in 1995. Many laboratory
studies performed on rodents have shown this hormone to be an extremely
powerful memory enhancer. The mechanism for this action is not fully known but
probably involves a number of mechanisms. One possibility is the effect of
Preg on the brain chemical acetylcholine, which is known to be involved with
memory.
In this study, pregnenolone was given to rats directly in the fluid bathing
the brain. Following Preg administration, there was an increase in
acetylcholine levels in the cerebrum. The increase in cortical acetylcholine
reached a maximum thirty minutes after administration. This result suggest
that Preg interacts with the cortical cholinergic system, which may account,
at least in part, for the memory-improving properties of this hormone.
Comments: The crucial role that hormones play in the brain is gradually being
discovered. Unfortunately there has been very little thus far on the role of
pregnenolone in human cognition. Thus, safe and effective dosages have not yet
been established. You will often find Preg sold in dosages of 5, 10, 25, 30,
50, and even 100 mg. Although the high dosages may be useful in certain
conditions when used temporarily under medical supervision, I urge both
consumers and health care practitioners to limit their dosages when taking
Preg for the long term. The appropriate dosages for long term use may be as
low as 1 to 3 mg. Preg is a powerful hormone and needs to be treated
cautiously.
Darnaudery M. The neurosteroid pregnenolone sulfate increases cortical
acetylcholine release: a microdialysis study in freely moving rats. J
Neurochem
1998 Nov;71(5):2018-22