EFFECTS OF CATECHOLAMINES AND 4-METHYLCATECHOL ON THE SYNTHESIS AND SECRETION OF NERVE GROWTH-FACTOR BY RAT SCIATIC-NERVE SEGMENTS IN CULTURE

Epinephrine (EN), norepinephrine (NE), and dopamine (DA) separately increased the nerve growth factor (NGF) content in both the conditioned medium (CM) and cultured rat sciatic nerve segments. The stimulation ofthe increase in NGF content was observed after an 8-h time lag. These observations suggest that catecholamines stimulate the de nova synthesis and secretion ofNGF protein in organ culture. The maximal effects were observed at limited concentrations such as 0.1-0.2 mM and weakened after 2 days. A similar effect was observed with 4-methylcatechol, a nonamine catechol compound, but not with adrenergic α or β agonists, indicating that adrenergic receptors do not participate in the stimulatory effect. In other words, catecholamines and/or some of their derivatives are able to stimulate NGF synthesis in cultured sciatic nerve. These findings suggest a physiological role for catecholamines and their derivatives to act as a stimulator ofNGF synthesis in end organs that are innervated by sympathetic neurons. © 1990, Biomedical Research Press. All rights reserved.