186 Brain Research, 214 (1981) 186-189 © Elsevier/North-Holland Biomedical Press Effect of nerve activity on transport of nerve growth factor and dopamine fl-hydroxylase antibodies in sympathetic neurones G. LEES*, I. CHUBB, C. FREEMAN, L. GEFFEN** and R. RUSH Department of Human Physiology, Centre for Neuroscience, The Flinders University of South Australia, Bedford Park, S.A. 5042 (Australia) (Accepted January 29th, 198t) Key words: nerve activity -- nerve growth factor -- dopamine fl-hydroxylase antibody -- sympathe- tic neuron The effect of nerve activity on the uptake and retrograde transport of nerve growth factor (NGF) and dopamine fl-hydroxylase (DBH) antibodies was studied by injecting l~5I-labelled NGF and anti-DBH into the anterior eye chamber of guinea-pigs. Decentralization of the ipsilateral superior cervical ganglion (SCG) had no significant effect on the retrograde transport of either NGF or anti- DBH. Phenoxybenzamine produced a 50 ~ increase in anti-DBH but not NG F accumulation and this effect was prevented by prior decentralization. This demonstrates that NGFis taken up independently of the retrieval of synaptic vesicle components. Nerve growth factor (NGF) is taken up selectively into sympathetic neurones and retrogradely transported to the cell body where it regulates inter alia the production of enzymes involved in transmitter synthesis. The saturable binding of NGF occurs at concentrations several orders of magnitude lower than that necessary to demonstrate the uptake of exogenous macromolecules such as horseradish peroxi- dase, suggesting that the sympathetic nerve terminals possess specific receptors for NGF2,L However, the location of these receptors and the mechanisms of internali- zation of NGF in nerve terminals is not known. One possibility is that NGF is taken up by synaptic vesicles after they have released transmitter, thereby providing a parsimonious mechanism for coupling activity of the nerves to their acquisition of NGF. This hypothesis has been examined by studying the effect of decentralization of sympathetic neurones on the uptake and transport of NGF 1~. No alteration was observed but in the absence of information about the basal exocytotic activity of the nerves before and after decentralization, these experiments do not establish the extent to which NGF uptake is dependent on vesicle retrieval, particularly when the nerves are active. We and others have previously demonstrated that the uptake and retrograde transport of antibodies to dopamine fl-hydroxylase (DBH), an enzyme that is a * Present address: Department of Psychiatry, University of Auckland, Auckland, New Zealand. ** To whom correspondence should be addressed.