Autapses and Networks of Hippocampal Neurons Exhibit Distinct Synaptic Transmission Phenotypes in the Absence of Synaptotagmin I

• DOI: 10.1523/jneurosci.1341-09.2009
• Publication Date: 2009-06-10T17:33:58Z
• Authors: H. Liu; C. Dean; C. P. Arthur; M. Dong; E. R. Chapman
• Keywords: Synaptotagmin 1; Synaptotagmin I

Synaptotagmin-I (syt-I) is required for rapid neurotransmitter release in mouse hippocampal neurons. However, contradictory results have been reported regarding evoked and spontaneous secretion from syt-I knock-out (KO) Here, we compared synaptic transmission two different neuron preparations: autaptic cultures which a single isolated cell innervates itself, dissociated mass individual cells are innervated by neighboring cells. In cultures, the total extent of release, size readily releasable pool vesicles, probability were unchanged KO contrast, containing multiple interconnected neurons, number docked probability, significantly reduced Using micronetwork system varied on an island, found that frequency vesicle fusion events (minis) was neurons when or fewer present island. micronetworks composed three more mini increased threefold to fivefold with wild type. Moreover, interneuronal synapses exhibited higher rates than synapses. This rate attributable increase because excitatory formed set per regardless connected Thus, aspects differ between phenotype, resulting loss syt-I, dictated connectivity