Intracellular and whole-cell patch-clamp recordings were obtained from sympathetic preganglionic neurons in rat spinal cord slices. Perfusion of selective ionotropic and metabotropic excitatory amino acid agonists induced depolarizing responses in all neurons. In approximately 20% of neurons the application of these agonists also evoked inhibitory postsynaptic potentials. The application of the...

Structural malformations of the cortex, arising as a result of genetic mutation or injury during development are associated with dyslexia, epilepsy, and other neurological deficits. We have used a rat model of a microgyral malformation to examine mechanisms of epileptogenesis. Our previous studies showed that the frequency of miniature excitatory postsynaptic currents (mEPSCs) recorded in neoco...

The balance between excitatory and inhibitory synapses is crucial for normal brain function. Wnt proteins stimulate synapse formation by increasing synaptic assembly. However, it is unclear whether Wnt signaling differentially regulates the formation of excitatory and inhibitory synapses. Here, we demonstrate that Wnt7a preferentially stimulates excitatory synapse formation and function. In hip...

Acute morphine exposure induces antinociceptive activity, but the underlying mechanisms in the central nervous system are unclear. Using whole-cell patch clamp recordings, we explore the role of morphine in the modulation of excitatory synaptic transmission in lateral amygdala neurons of rats. The results demonstrate that perfusion of 10 microM of morphine to the lateral amygdala inhibits the d...

Rett Syndrome (RTT) is a devastating neurological disorder that is caused by mutations in the MECP2 gene. Mecp2-mutant mice have been used as a model system to study the disease mechanism. Our previous work has suggested that MeCP2 malfunction in neurons is the primary cause of RTT in the mouse. However, the neurophysiological consequences of MeCP2 malfunction remain obscure. Using whole-cell p...

Neurons receive thousands of synaptic inputs throughout elaborate dendritic trees. Here we determine the somatic impact of excitatory postsynaptic potentials (EPSPs) generated at known dendritic sites in neocortical pyramidal neurons. As inputs became more distal, somatic EPSP amplitude decreased, whereas use-dependent depression increased. Despite marked attenuation (>40-fold), when coactivate...

Transient pairwise synchronization of locust antennal lobe (AL) projection neurons (PNs) occurs during odor responses. In a Hodgkin-Huxley-type model of the AL, interactions between excitatory PNs and inhibitory local neurons (LNs) created coherent network oscillations during odor stimulation. GABAergic interconnections between LNs led to competition among them such that different groups of LNs...

In 1965, H. T. Hammel proposed a neuronal model to explain set-point thermoregulation. His model was based on a synaptic network encompassing four different types of hypothalamic neurons: i.e., warm-sensitive and temperature-insensitive neurons and heat loss and heat production effector neurons. Although some modifications to this model are suggested, recent electrophysiological and morphologic...

Paired intracellular recordings with biocytin labelling were made in slices of adult rat somatosensory and visual cortex and in cat visual cortex to examine the properties of synaptic connections made by layer 6 pyramidal cells, to determine whether cortico-cortical pyramids more commonly provide input to other layer 6 pyramids than cortico-thalamic cells, and whether these connections exhibit ...

The ring of a neuron in a biological neural system causes in certain other neurons excitatory postsynaptic potential changes (EPSP's) that are not \rectangular", but have the form of a smooth hill. We prove in this article for a formal model of a network of spiking neurons, that the rising respectively declining segments of these EPSP's are in fact essential for the computational power of the m...