Evidence for transmitter operated electrical synapses (TOES) in ampullary electroreceptor organs.

Afferent fibres of ampullary electroreceptor organs in electrosensitive fish fire spontaneously, that is, they fire without external stimulus. In the past it has been postulated that the spontaneous activity originates from a sustained level of neurotransmitter release delivered by the electroreceptor cells. The spontaneous activity can be modulated by electrical stimuli.

Cannabinoid agonist WIN 55212-2 speeds up the cone response to light offset in goldfish retina.

Goldfish cones contain CB1 receptors at the synaptic terminal, selectively accumulate 3H-anandamide, and contain fatty acid amide hydrolase-immunoreactivity, and voltage-gated calcium and potassium currents are modulated by CB1 ligands (Yazulla et al., 2000; Fan & Yazulla, 2003; Glaser et al., 2005).