Rodent noradrenergic chromaffin cells contain calbindin D28K immmunoreactivity.

The calcium binding protein calbindin D28K is heterogeneously distributed in neurons throughout the body. We have investigated the distribution of calbindin in the chromaffin cells of the adult rodent adrenal medulla, which share the same developmental origin as peripheral sensory and autonomic neurons. Calbindin immunoreactivity was present in all noradrenergic chromaffin cells (defined by their lack of the adrenaline synthesizing enzyme, phenylethanolamine N-methyl transferase) in both the rat and mouse. It was also present in a very few adrenergic chromaffin cells in both rat and mouse. Calbindin-immunoreactivity is present in rat noradrenergic chromaffin cells from the day of birth and so is a useful marker for identifying rodent noradrenergic chromaffin cells.