The involvement of the cGMP-protein kinase G (PKG) signaling pathway in the induction of long-term depression (LTD) and long-term potentiation (LTP) was investigated in the medial perforant path of the dentate gyrus in vitro. Low-frequency stimulation (LFS)-induced LTD of field EPSPs was inhibited by bath perfusion of the selective soluble guanylyl cyclase inhibitor 1H-[1,2,4] oxadiazolo[4,3, -...

The establishment of the adult innervation of Purkinje cells (PCs) by climbing fibers (CFs) was studied in the cerebellar vermis of the developing rat. Excitatory postsynaptic potentials (EPSPs) evoked in PCs by activation of the climbing fibers (CF-EPSPs) were recorded intracellularly from a total of 310 cells in young rats aged from 3 to 15 postnatal days. The CF system was activated by elect...

Amplitudes of EPSPs evoked by repetitive presynaptic action potentials can either decrease (synaptic depression) or increase (synaptic facilitation). To determine whether facilitation and depression in the connections between neocortical pyramidal cells varied with the identity of the pre- or the postsynaptic cell and whether they changed during postnatal development, whole-cell voltage recordi...

The ability to fuel neurons via glycogenolysis is believed to be an important function of glia. Indeed, the slow, rather than immediate, depression of synaptic transmission in hippocampal slices during exogenous glucose deprivation suggests that intrinsic energy reservoirs help to sustain neurotransmission. It is believed that glia fuel neighboring neurons via diffusible monocarboxylates such a...

The present study examined synaptic potentials of neurons in inferior colliculus (IC) cortex slice and the roles of GABA and glutamate receptors in generating these potentials. Multipolar (82%) and elongated (18%) cells were observed with intracellular biocytin staining. Electrical stimulation of the IC commissure (CoIC) elicited only inhibitory postsynaptic potentials (IPSPs) (10% of cells), o...

Although synaptic properties are specific to the type of synapse examined, there is evidence to suggest that properties can vary in individual synaptic populations. Here, a large sample of monosynaptic connections made by excitatory interneurons (EINs) onto motor neurons in the lamprey spinal cord locomotor network has been used to examine the properties of a single class of spinal synapse in d...

Intracellular recording and extracellular field potential (FP) recordings were obtained from spinal cord dorsal horn neurons (laminae I-IV) in a rat transverse slice preparation with attached dorsal roots. To study changes in synaptic inputs after neuroma formation, the sciatic nerve was sectioned and ligated 3 weeks before in vitro electrophysiological analysis. Horseradish peroxidase labeling...

Understanding evolutionary interactions among crops and weeds can facilitate effective weed management. For example, gene flow from crops to their wild or weedy relatives can lead to rapid evolution in recipient populations. In rice (Oryza sativa), transgenic herbicide resistance is expected to spread to conspecific weedy rice (Oryza sativa f. spontanea) via hybridization. Here, we studied fitn...

We tested the hypothesis that neurotrophin-3 (NT-3) in adult cats can rescue the central synapses made by muscle afferents from the effects of peripheral axotomy. The medial gastrocnemius (MG) muscle nerve in cats was axotomized and capped or axotomized and the distal end provided with either saline or NT-3 by mini-osmotic pump. Four to five weeks later monosynaptic excitatory postsynaptic pote...

Weed resistance to herbicides is a natural phenomenon that exerts selection on individuals in a population. In Brazil, glyphosate resistance was recently detected in Digitaria insularis. The objective of this study was to elucidate mechanisms of weed resistance in this plant, including genetic variability, allelism, amino acid substitutions, gene expression, and enzymatic activity levels. Most ...