Ammonia and PD?
 

My thanks go to soccertese for stating a thread on the work of Freed on, amongst other things, sodium phenylbutyrate. Following its reported success in mice, it is under trial as a possible treatment for PD.

It seems to me that this result adds weight to the possibility that ammonia plays a part in the etiology of PD.

Sodium phenylbutyrate is "used to treat urea cycle disorders" [1]. "The urea cycle involves a series of biochemical steps in which nitrogen, a waste product of protein metabolism, is removed from the blood and converted to urea. Normally, the urea is transferred into the urine and removed from the body. In urea cycle disorders, the nitrogen accumulates in the form of ammonia, a highly toxic substance, and is not removed from the body." [2]

A link between ammonia and PD is consistent with the epidemiological data. Here are links to three maps of the US which show county by county values for air quality [3], ammonia emissions [4] and the incidence of Parkinson's [5].

As Rick pointed out some time ago h. pylori generates ammonia in the gut [6]. Dobbs et al have shown that removing h. pylori can reduce PD symptoms in some patients [7].

Not conclusive, but worth a thought?

I'll be grateful for any comments.

[1] http://en.wikipedia.org/wiki/Sodium_phenylbutyrate
[2] http://en.wikipedia.org/wiki/Urea_cycle_disorder
[3] http://www.creativemethods.com/airqu...ted_states.htm
[4] http://www.esrl.noaa.gov/csd/aqrs/reports/ammonia.pdf
[5] http://www.ncbi.nlm.nih.gov/pmc/arti...395/figure/F2/
[6] http://en.wikipedia.org/wiki/Helicobacter_pylori
[7] http://www.whatsdrivingparkinsons.net/pdf/1.pdf

John

Very interesting, John. Thanks for the extensive documentation.