Or maybe there isn't always a loss of dopa cells just not working dopa cells.
Or maybe there are other neurotransmitters involved besides dopamine.
( wouldn't that be embarrassing after decades of research and millions invested)

Joking apart, whilst I'm in agreement with all the above what's needed is imagination as much as intellect, the ability to dare, to think outside the box that's when scientific breakthroughs occur ! Not tweaking and modifying the same theories for 60 years. It strikes me there is a fundamental flaw somewhere.

Wow I wrote that calmly ! Without drama probably because I've reduced the dopamine agonist, so called because Glaxokline think it's the most likely explanation for how it works..!

Parkinsonia, a land of smoke and mirrors.

Stay frosty people

Nigel