Retrograde Signaling in LTP - Formal Definition of A Retrograde Neurotransmitter

Formal Definition of A Retrograde Neurotransmitter

In 2009, Regehr et al. proposed criteria for defining retrograde neurotransmitters. According to their work, a signaling molecule can be considered a retrograde neurotransmitter if it satisfies all of the following criteria:

• The appropriate machinery for synthesizing and releasing the retrograde messenger must be located in the postsynaptic neuron

• Disrupting the synthesis and/or release of the messenger from the postsynaptic neuron must prevent retrograde signaling

• The appropriate targets for the retrograde messenger must be located in the presynaptic bouton

• Disrupting the targets for the retrograde messenger in the presynaptic boutons must eliminate retrograde signaling

• Exposing the presynaptic bouton to the messenger should mimic retrograde signaling provided the presence of the retrograde messenger is sufficient for retrograde signaling to occur

• In cases where the retrograde messenger is not sufficient, pairing the other factor(s) with the retrograde signal should mimic the phenomenon