Inhibitory glycinergic neurotransmission in the mammalian auditory brainstem upon prolonged stimulation: short-term plasticity and synaptic reliability.

摘要: Short-term plasticity plays a key role in synaptic transmission and has been extensively investigated for excitatory synapses. Much less is known about inhibitory Here we analyze the performance of glycinergic connections between medial nucleus trapezoid body (MNTB) lateral superior olive (LSO) auditory brainstem, where high spike rates as well fast precise neurotransmission are hallmarks. Analysis was performed acute mouse slices shortly after hearing onset (postnatal day (P)11) eight days later (P19). Stimulation done at 37°C with 1–400 Hz 40 s. Moreover, novel approach named marathon experiments, very prolonged stimulation protocol employed, comprising 10 trials 1-min challenge recovery periods 50 1 Hz, respectively, thus lasting up to 20 min amounting > 30,000 stimulus pulses. IPSC peak amplitudes displayed short-term depression (STD) attenuation frequency-dependent manner. No facilitation observed. STD MNTB-LSO pronounced than reported upstream calyx Held-MNTB connections. At P11, level failure rate were slightly lower within ms-to-s range P19. During s, P19 sustained virtually failure-free frequencies 100 whereas P11 did so only Hz. In synapses recuperated reproducibly from during all periods, demonstrating robust machinery onset. 26°C, severely impaired comprised abnormally minutes silence, indicative imprecisely regulated vesicle pools. Our study takes fresh look stability by extending conventional minutes. It also provides framework future analyses plasticity.