Hypertension drugs that block calcium ionic channels inside the substantia nigra or SN region of the brain prevent Parkinson's disease in humans.

James Surmeier, who belongs to the research team that published this research, is promoting the calcium blocker isradipine, currently in phase II of clinical trials. This drug will be useful for people in the risk group and early stage of Parkinson's.

The chief cause of Parkinson’s is attributed to calcium's ability to damage "pacemaking cells" that release pulses of hormone dopamine. Disturbances in movement and balance occur with tremors and stiffness characteristic of this disease.

Jaime Guzman from Northwestern University in Chicago explained the reason for greater susceptibility of SN region alone. They identified calcium as the culprit by comparing the pacemaking SN region and a non-pacemaking region of brain in mice. Cell damage in SN region occurs by calcium influx into the SN cells causing oxidative stress from release of free radicals that kill DNA and proteins.

Since it was known that calcium channels are not essential to pacemaking, scientists went ahead and tested if these channels are necessary. Calcium channel blocking drugs were administered to mice with Parkinson's to allow for pacemaking activity alone. Parkinson's mice lacked gene DJ-1 and showed greater degree of damage to dopamine releasing cells than normal mice. With drug treatment, the cell damage to SN region dropped to levels seen in other oxidative stress resistant types of brain cells.

This novel experimental result comes in support of previous study by Christoph Meier at University Hospital Basel in Switzerland. Dr. Meier demonstrated that hypertension drugs that are specifically calcium channel blocking reduced risk of Parkinson's disease.

"A lot seems to point towards a potential benefit of calcium-channel blockers in Parkinson's disease, but it's too early to tell whether they help prevent the disease or could improve the situation of patients who already have a diagnosis," he said.,