Journal of Neurophysiology, Vol 42, Issue 5 1426-1436, Copyright © 1979 by APS
Postnatal rat sympathetic neurons in culture. II. Synaptic transmission by postnatal neurons
E. Wakshull, M. I. Johnson and H. Burton
1. It was shown in the preceding paper that postnatally derived rat
superior cervical ganglion neurons (SCGN) will grow in dissociated cell
culture and form functional synaptic connections with each other. In this
report, synaptic transmission by the postnatal SCGN is detailed. 2.
Synaptic interactions between SCGN were blocked by the nicotinic
cholinergic antagonist hexamathonium (C-6), indicating that acetylcholine
was the transmitter substance used by these neurons. This was found to be
the case even for neurons taken from 12.5-wk-old animals. 3. In a few
cases, the beta-adrenergic blocking agent, propranolol, was found to block
synaptic potentials, suggesting that a catecholamine might be involved in
the transmission process. The possible mechanisms of this involvement are
discussed. 4. SCGN taken from up to 10-wk-old rats were able to form
functional synaptic contacts with cocultured skeletal muscle cells. These
interactions were sensitive to low external Ca2+ and to 1--2 microM
d-tubocurarine (d-TC). 5. It is concluded that even adult SCGN retain a
certain amount of neurotransmitter "plasticity" when grown under
appropriate culture conditions. From the data on the neuron-neuron and
SCGN-skeletal muscle interactions, it is suggested that a matching of
presynaptic transmitter with postsynaptic receptor is a sufficient
condition for the formation of functional nerve-target interactions.
