The actions of L-glutamate on the postsynaptic membrane of the squid giant synapse were investigated using two methods of application: ionophoresis and bath perfusion. Bath perfusion of 10 mmoll-1 sodium glutamate did not produce an appreciable depolarization of the postsynaptic membrane but reversibly blocked the neurally evoked postsynaptic potential (PSP). The postsynaptic membrane depolariz...

the activity of the magnocellular neurons (mcns) of supraoptic nucleus (son) is regulated by a variety of excitatory and inhibitory inputs. opioids are one of the important compounds that affect these inputs at son synapses. in this study, whole-cell patch clamp recording of son neurons was used to investigate the effect of acute and repeated morphine administration on spontaneous inhibitory an...

1. An in vitro slice preparation of rat prefrontal cortex was used to analyse the responses of layer V pyramidal cells to electrical stimulation of layer II. We also studied the long-lasting modifications of synaptic efficacy following high-frequency stimulation of the same region. 2. Stable intracellular recordings were obtained from forty-three regular spiking pyramidal cells. The input resis...

Pauses in the tonic firing of striatal cholinergic interneurons (CINs) emerge during reward-related learning in response to conditioning of a neutral cue. We have previously reported that augmenting the postsynaptic response to cortical afferents in CINs is coupled to the emergence of a cell-intrinsic afterhyperpolarization (AHP) underlying pauses in tonic activity. Here we investigated in a bi...

Progressive supranuclear palsy (PSP) is a degenerative condition of unknown aetiology that produces an akinetic-rigid form of parkinsonism characterised by early falls and abnormalities of extraocular movements. Mean age of onset is approximately 63 years, and mean survival from symptom onset is 9 years. Men are much more frequently affected than women. The classic clinical finding is supranucl...

When an action potential is transmitted to a postsynaptic neuron, a small change in the postsynaptic neuron’s membrane potential occurs. These small changes, known as a postsynaptic potentials (PSPs), are highly variable, and current models assume that this variability is corrupting noise. In contrast, we show that this variability could have an important computational role: representing a syna...

The ability of ecosystems to adapt to environmental perturbations depends on the duration and intensity of change and the overall biological diversity of the system. While studies have indicated that rare microbial taxa may provide a biological reservoir that supports long-term ecosystem stability, how this dynamic population is influenced by environmental parameters remains unclear. In this st...

Cortico-striatal spike-timing dependent plasticity (STDP) is modulated by dopamine in vitro. The present study investigated STDP in vivo using alternative procedures for modulating dopaminergic inputs. Postsynaptic potentials (PSP) were evoked in intracellularly recorded spiny neurons by electrical stimulation of the contralateral motor cortex. PSPs often consisted of up to three distinct compo...

Synaptic transmission between pairs of neurons in layer 2/3 of in vitro slices from the rat visual cortex was studied by dual intracellular recording. The intrinsic electrophysiological properties of these neurons suggested that they were pyramidal cells. More than 1/3 of the total number of synaptically connected neurons were stained by intracellular iontophoresis of biocytin, and all had pyra...

Short-term synaptic depression and facilitation often are elicited by different temporal patterns of activity. Short-term plasticity may contribute, therefore, to temporal filtering by impeding synaptic transmission for some temporal patterns of activity and facilitating transmission for other patterns. We examined this hypothesis by investigating whether short-term plasticity contributes to th...