1. Serotonin (5-HT) facilitates the connections between sensory and motor neurons in Aplysia during behavioural sensitization. The effect of 5-HT on sensorimotor synapses is believed to be primarily presynaptic. Here we tested whether 5-HT can have an exclusively postsynaptic facilitatory effect. 2. Siphon motor neurons were individually dissociated from the abdominal ganglion of Aplysia and pl...

Chronic flurazepam treatment substantially impairs the function of GABAergic synapses on hippocampal CA1 pyramidal cells. Previous findings included a significant decrease in the synaptic and unitary conductance of CA1 pyramidal neuron GABA(A) receptor channels and the appearance of a GABA(A)-receptor mediated depolarizing potential. To investigate the ionic basis of the decreased conductance, ...

Principal cells in the medial nucleus of the trapezoid body (MNTB) are believed to be critical components in the circuit subserving sound localization. These cells, located in the superior olivary complex, convert excitatory inputs, arriving from the contralateral cochlear nucleus by way of large somatic synapses (the calyces of Held), to inhibitory projections onto principal cells in the ipsil...

N-methyl-D-aspartate receptors (NMDAR) are crucial for the function of excitatory neurotransmission and are present at the synapse and on the extrasynaptic membrane. The major nucleus of the basal ganglia, striatum, receives a large glutamatergic excitatory input carrying information about movements and associated sensory stimulation for its proper function. Such bombardment of glutamate synapt...

Preclinical studies suggest that substance P (SP) neurokinin 1 (NK1) receptor antagonists are efficient in the treatment of anxiety and depression. This therapeutic activity could be mediated via stimulation of serotonin (5-HT) neurons located in the dorsal raphe nucleus (DRN), which receive important SP-NK1 receptor immunoreactive innervations. The present study examined the effects of intrara...

Recordings were obtained from dorsal column nucleus (DCN) neurons in a neonatal rat brain stem-spinal cord preparation to study their basic electrophysiological properties and responses to stimulation of a dorsal root. Whole-cell patch-clamp recordings were made from 21 neurons that responded to dorsal root stimulation with a fast excitatory postsynaptic potential (EPSP). These neurons were loc...

Mastication can be triggered by repetitive stimulation of the cortex or of sensory inputs, but is patterned by a brain stem central pattern generator (CPG). This CPG may include the dorsal part of the principal trigeminal sensory nucleus (NVsnpr), where neurons burst repetitively when the extracellular concentration of Ca(2+) ([Ca(2+)](e)) drops. We examined the effects of repetitive stimulatio...

PURPOSE The transition from an interictal to an ictal pattern of epileptiform activity is a strategic target for antiepileptic drug (AED) action. Both the muscarinic agonist pilocarpine and the selective group I metabotropic glutamate receptor (mGluR) agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) produce prolonged synchronous activity in the hippocampal slice that resembles ictal discharges. W...

38 The parallel fibers (PFs) in the cerebellar cortex extend several millimeters along a folium in the 39 medio-lateral direction. The PFs are orthogonal to and cross several parasagittal zones defined by 40 the olivocerebellar and corticonuclear pathways and the expression of molecular markers on 41 Purkinje cells (PCs). The functions of these two organizations remain unclear, including 42 whe...

How localized synaptic input regulates dendritic branch structure is not well understood. For these experiments, we used single-cell electroporation, live cell imaging, in vitro deafferentation, pharmacology, and electrophysiological stimulation to study how local alterations in synaptic input affect dendritic branch structure in nucleus laminaris (NL). We found that interrupting or modulating ...