BDNF Switches Neuronal Output

Science's STKE  04 Jun 2002:
Vol. 2002, Issue 135, pp. tw196-TW196
DOI: 10.1126/stke.2002.135.tw196

Increasing evidence indicates that single neurons can use more than one neurotransmitter. When the neurotransmitters are stored in different kinds of vesicles, release can be differentially regulated. However, in rat neonatal sympathetic neurons, norepinephrine and acetylcholine (which have excitatory and inhibitory effects on cardiac myocytes, respectively) are produced and are presumably both stored in similar synaptic vesicles. Yang et al. show that, in cultures of such neurons with cardiac ventricular myocytes, electrical stimulation of the neurons normally produces an excitatory signal (mediated by norepinephrine) that increases the beat rate of the innervated myocytes. However, when the cells were briefly (15 min) treated with the neurotrophic factor BDNF (brain-derived neurotrophic factor), neuronal stimulation produced an opposite, inhibitory effect on beating of the myocytes. The effect of BDNF appeared to be mediated by the low-affinity p75 neurotrophin receptor. It remains unclear exactly how BDNF signals enhance neurotransmission to the muscle cells by acteylcholine and blunt that of norepinephrine, but the results demonstrate that the neuronal signal can be modulated and even reversed, thus providing a new mechanism for control of synaptic plasticity during development.

B. Yang, J. D. Slonimsky, S. J. Birren, A rapid switch in sympathetic neurotransmitter release properties mediated by the p75 receptor. Nature Neuro. 5, 539-545 (2002). [Online Journal]