Send to

Choose Destination
Neuron. 1991 Jan;6(1):145-51.

Target contact regulates the calcium responsiveness of the secretory machinery during synaptogenesis.

Author information

Department of Zoology and Genetics, Iowa State University, Ames.


Neuron B19 of Helisoma is selective in synaptogenesis. Presynaptic mechanisms underlying this selectivity were tested. Acetylcholine-sensitive assay cells were micromanipulated into contact with B19 somata to assess its secretory state. Prior to appropriate muscle target contact, spontaneous synaptic currents were detected; however, action potential-evoked release of neurotransmitter was detected only following hours of muscle contact. Photolysis of a calcium cage, DM-nitrophen, accelerated the frequency of synaptic currents in muscle-contacted, but not novel neuron-contacted, B19 somata. These studies demonstrate that contact with appropriate target muscle enhances the responsiveness of this neuron's secretory machinery to internal calcium levels, thereby imparting the presynaptic cell with the ability to couple action potentials with neurotransmitter release.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center