Neil,

Good question - I think one of the hopes of Isradipine (calcium channel blocker) is that by blocking the calcium from irritating the (non-)dopamine producing cells, that those cells would (eventually) rejuvenate - and start producing dopamine again. (I'm not sure what stage the clinical trial for Isradipine is in now)

I've been taking Isradipine for about 18 months now - and nothing miraculous for me so far. But what if this works but it takes 5 years before the cells start repairing themselves? I'm in it for the long haul. I still have hope for this to work. (I'm a "white lab rat" -- but my neurologist is happy to prescribe Isradipine since I have hypertension. Who would have imagined that would be a good thing?)