Retrograde signaling at GABAA-receptor synapses in the mammalian CNS.
Recent studies have emphasized the role of signals that travel from a target cell, in a retrograde direction, to cells that synapse on the target and influence their output. While the focus of most research on this topic has been on long-lasting alterations at excitatory synapses, evidence that implicates retrograde transmission in the transient reduction of GABAA-receptor-mediated inhibition in hippocampus and cerebellum has begun to accumulate. Brief depolarizations of the postsynaptic principal cells lead to increases in the intracellular concentration of Ca2+, and a reduction in GABAA-receptor-mediated responses for 1-2 min. No concomitant reduction in postsynaptic GABAA-receptor responsiveness has been detected. Rather, release of GABA from inhibitory-interneuron terminals appears to be reduced. The properties of this 'depolarization-induced suppression of inhibition' might be appropriate for unique physiological roles.
D000818:Animals; D002490:Central Nervous System / Q000502:physiology*; D006801:Humans; D011963:Receptors, GABA-A / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D013569:Synapses / Q000502:physiology*
D011963:Receptors, GABA-A