substantia niger it's involvement or not in the dopaminergic activites in the brain

[ron45]

I saw some posts on this forum that led me to believe some of the moderators and members are very well read in neuroscience and the associated chemistry. I read some on these subjects and can even glean a little information from research papers...... sometimes.

My question comes from reading about Deprenyl in Smart Durgs II after I became interested in finding out why my concentration and focus is out the window. I turned 70 in april so there is that. Smart Drugs II
said something like deprenyl is the only drug known to selectively target the substantia nigra, and that dep. plays an active role in protecting/rejuvenating that little mass of tissue.

A few weeks ago In Discover mag. I read a long article on the dopaminergic system and it's effect on learning. Nowhere was the substanita nigra mentioned. This mag is no paragon of scientific information but still......

Because I accepted the info in Smart Drugs II, I expected to see their assertions gain some more exposure..... Hence my rambling question Is S.D.II correct in what the Dr. and non phd chemist have say about substantia nigra's active role in dopamine chemistry and the assertion that deprenyl is the hot damn brain booster of all time?

Thank you for your time,

Ron

 

[serotonin2A]

The substantia nigra (SN) is one of the nuclei where dopamine containing cells are found. Those cells are involved in learning and cognition but their primary function is to regulate movement via their projections to the basal ganglia (SN is the primary region where neurodegeneration occurs in Parkinson's disease).

Deprenyl will increase dopamine in SN but it does not selectively target that region. Deprenyl can help with some conditions were there is insufficient dopamine in the SN but it doesn't seem to improve executive and cognitive function above baseline/normal levels. There is some evidence that it may be neuroprotective to dopaminergic cells (probably because it can block oxidative stress and certain neurotoxins) but it doesn't reverse cell loss.

 

[Cotcha Yankinov]

http://www.benbest.com/lifeext/deprenyl.html
A lot of Deprenyl's action is by inhibiting MAO-B, which is what metabolizes dopamine among other things. From wiki- Alzheimer's disease and Parkinson's disease are both associated with elevated levels of MAO-B in the brain. The normal activity of MAO-B creates reactive oxygen species, which directly damage cells. MAO-B levels have been found to increase with age, suggesting a role in natural age related cognitive decline and the increased likelihood of developing neurological diseases later in life.

Deprenyl seems to be protective against neurodegeneration mostly, delaying the need for other parkinsons drugs for a little while in those that are progressing and making other parkinsons drugs (L-DOPA) more efficient when used together.
http://www.ncbi.nlm.nih.gov/pubmed/10343976 - Aromatic L-amino acid decarboxylase is what (among many other conversions) takes L-DOPA and converts it into dopamine, and deprenyl appears to increase that conversion in the substantia nigra.

A lot of this deprenyl "amazing drug" research seems to relate to models of parkinsons though, so its hard to say if someone without parkinsons would benefit the same because they have different brain chemistry and something else could be bottlenecking a normal person's focus. I suppose specific to your situation the question in my mind is why are you having trouble with focus in the first place? I'm sure taking something like Ritalin or maybe a MAO-B inhibitor would help you focus no matter what the real source of your problem is (maybe making things worse in the long run regarding stims like ritalin) but I think the root cause is important. Is it your sleep becoming more fragmented as you get older? (which happens to everybody but is a hallmark of most neurodegenerative disease by the way) Is sleep apnea contributing? Are we seeing the beginning of a neurodegenerative disease like alzheimer's/parkinsons/dementia/lewy body dementia? If you haven't had one yet I would highly recommend getting a sleep study done (My area is sleep so I am biased towards this but I promise you your sleep is imperative). Just wondering, from your point of view what is your sleep like and also what is your drug use history like?