Inhibitory cotransmission or after-hyperpolarizing potentials can regulate firing in recurrent networks with excitatory metabotropic transmission

Abstract

Recurrent networks of neurons communicating via excitatory connections are common in the nervous system. In the absence of mechanisms to control firing (collectively termed negative feedback), these networks are likely to be bistable and unable to meaningfully encode input signals. In most recurrent circuits, negative feedback is provided by a specialized subpopulation of interneurons, but such neurons are absent from some systems, which therefore require other forms of negative feedback. One such circuit is found within the enteric nervous system of the intestine, where AH/Dogiel type II neurons are interconnected via excitatory synapses acting through metabotropic receptors to produce slow..