transsynaptischer

The term *transsynaptisch* (German for "transsynaptic") refers to processes or effects that occur across synapses, the specialized junctions between neurons that facilitate communication in the nervous system. Transsynaptic mechanisms describe how signals are transmitted from one neuron to another via neurotransmitters, influencing neural activity and connectivity over multiple synaptic connections.

In neuroscience, transsynaptic signaling plays a critical role in synaptic plasticity—the ability of synapses to strengthen or weaken over time, which underlies learning and memory. For example, retrograde signaling, where a postsynaptic neuron sends signals back to the presynaptic neuron, is a key transsynaptic process. This can modulate neurotransmitter release, affecting downstream neural circuits.

Transsynaptic effects are also relevant in pathological conditions, such as neurodegenerative diseases or psychiatric disorders. For instance, misregulation of transsynaptic signaling may contribute to abnormal neural connectivity in conditions like Alzheimer’s disease or schizophrenia. Research in this area often involves tracing neural pathways or studying how viral vectors or proteins spread between neurons.

The term is frequently used in experimental neuroscience, particularly in studies employing tract-tracing techniques or optogenetics, where researchers observe how signals propagate across multiple synapses. Understanding transsynaptic mechanisms helps clarify how neural circuits are wired and how they adapt to environmental or pathological changes.