The active form of B6 is P-5-P:
en.wikipedia.org
Role as a coenzyme
PLP acts as a coenzyme in all
transamination reactions, and in certain
decarboxylation,
deamination, and
racemization reactions of
amino acids.<a href="
Pyridoxal phosphate - Wikipedia"><span>[</span>6<span>]</span></a> The aldehyde group of PLP forms a
Schiff-base linkage (internal
aldimine) with the ε-amino group of a specific lysine group of the
aminotransferase enzyme. The α-amino group of the amino acid substrate displaces the ε-amino group of the active-site lysine residue in a process known as transaldimination. The resulting external aldimine can lose a proton, carbon dioxide, or an amino acid sidechain to become a quinonoid intermediate, which in turn can act as a nucleophile in several reaction pathways.
In transamination, after deprotonation the quinonoid intermediate accepts a proton at a different position to become a
ketimine. The resulting ketimine is hydrolysed so that the amino group remains on the complex.<a href="
Pyridoxal phosphate - Wikipedia"><span>[</span>7<span>]</span></a> In addition, PLP is used by aminotransferases (or transaminases) that act upon unusual sugars such as
perosamine and
desosamine.<a href="
Pyridoxal phosphate - Wikipedia"><span>[</span>8<span>]</span></a> In these reactions, the PLP reacts with
glutamate, which transfers its alpha-amino group to PLP to make pyridoxamine phosphate (PMP). PMP then transfers its nitrogen to the sugar, making an
amino sugar.
PLP is also involved in various beta-elimination reactions such as the reactions carried out by
serine dehydratase and
GDP-4-keto-6-deoxymannose-3-dehydratase (ColD).<a href="
Pyridoxal phosphate - Wikipedia"><span>[</span>8<span>]</span></a>
It is also active in the condensation reaction in
heme synthesis.
PLP plays a role in the conversion of levodopa into dopamine, facilitates the conversion of the excitatory neurotransmitter glutamate to the inhibitory neurotransmitter GABA, and allows SAM to be decarboxylated to form propylamine, which is a precursor to polyamines.
Effects on Prolactin
Once vitamin B6 is converted to P-5-P, it increases dopamine in the brain. The rise in dopamine lowers prolactin [43].
Bodybuilders report benefits from P-5-P during or after cycles. Anecdotally, it helps prevent gynecomastia (abnormal breast growth) by lowering prolactin levels. Some prefer it over taking L-DOPA.
One pilot study suggests they might be right. In six healthy people, vitamin B6 infusions before exercise increased growth hormone levels and decreased prolactin levels, compared with placebo.
Try 250 MG of P-5-P and 500 MG of L-Tyrosine. Avoid other stimulants while taking this as it may exacerbate the effects. This really helps with orgasm intensity.
