6-Hydroxydopamine hydrobromide

I used the 6-Hydroxydopamine (6-OHDA) to deplete dopaminergic cells from the mouse brain, which is largely used as an experimental model of Parkinson's Disease. The 6-OHDA was injected into the mouse striatum and 21 days later we observed that the dopaminergic neurons (positive for tyrosine hydroxylase immunofluorescence) were almost absent in the substantia nigra pars compacta (SNc) from the 6-OHDA injected hemisphere (on the left). As a control for analytical comparisons, we also injected PBS into the contralateral hemisphere (on the right). When this neurotoxin is injected into striatum, as in this case, there is only a slight depletion of dopaminergic neurons from the ventral tegmental area (the region located into the middle of the image). The animals injected with 6-OHDA display several motor dysfunctions and are used to study the pathology and therapies for Parkinsonian symptoms.

Although 6-Hydroxydopamine hydrobromide (6-OHDA.HBr #2547) dissolves very well in aqueous solutions, some tips are necessary to guarantee its stability for biological experiments. 1. When calculating the 6-OHDA concentration, take in consideration that the doses that are often reported are for the free base and not for the hydrobromide (HBr) conjugated salt. Thus, in the case of 6-OHDA.HBr (#2547), the presence of HBr has to be taken into account in making the proper solution. HBr has a molecular weight of 80.91 and represents 32.352% of the 6-OHDA.HBr (#2547) molecular mass.2. Always dissolve the 6-OHDA salt in buffers containing antioxidant capacity. I suggest adding 1 mM ascorbic acid (#4055) into PBS. I know some colleagues that have used sodium metabisulfite as well with great success.3. Always make fresh solutions. The 6-OHDA solution is extremely prone to oxidation, even when resuspended in antioxidant buffers. When fresh, it looks dark red. However, it turns to brown after a few hours.4. Finally, 6-OHDA is extremely toxic. Therefore always be cautious when handling it.