COEXPRESSION OF GAP-43 WITH DOPAMINE-BETA-HYDROXYLASE IN ADULT-RAT SPINAL-CORD

DUAL colour immunofluorescence was used to compare the distribution of dopamine-beta-hydroxylase (DBH) and GAP-43 in the spinal cord of the adult rat. GAP-43 immunostaining was observed in all spinal cord regio ns containing DBH immunoreactivity. DBH and GAP-43 double-labelled fib res and varicosities were present in the lateral and ventral funiculi of the white matter and in the ventral horn where they were most promi nent around motoneurones. In the dorsal horn and around the central ca nal, GAP-43 immunoreactivity was too abundant to determine whether DBH immunoreactive fibres were double labelled. We conclude that the nora drenergic system is one of a small number of spinal cord systems that express high basal levels of GAP-43 in the adult.