Magnocellular neurons (MCNs) of the hypothalamic supraoptic nucleus (SON) secrete vasopressin and oxytocin. With the use of whole-cell and nystatin-perforated patch recordings of MCNs in current- and voltage-clamp modes, we show that high-frequency stimulation (HFS, 10-200 Hz) of excitatory afferents induces increases in the frequency and amplitude of 2,3-dioxo-6-nitro-1,2,3, 4-tetrahydrobenzo(...

The properties of synaptic transmission have been studied at the cyto-neural junction of the frog labyrinth posterior canal by examining excitatory postsynaptic potential (EPSP) activity recorded intraaxonally from the afferent nerve after abolishing spike firing by tetrodotoxin. The waveform, amplitude, and rate of occurrence of the EPSPs have been evaluated by means of a procedure of fluctuat...

The ovarian steroids exert both long-term and short-term actions on neurons involving different cellular mechanisms. We have investigated the long-term and short-term effects of estrogen on the electrophysiological properties of CA1 neurons utilizing intracellular recordings in hippocampal slices prepared from ovariectomized female rats. An in viva estrogen-priming paradigm was used to examine ...

Activation of postsynaptic alpha-calcium/calmodulin-dependent protein kinase II (alphaCaMKII) by calcium influx is a prerequisite for the induction of long-term potentiation (LTP) at most excitatory synapses in the hippocampus and cortex. Here we show that postsynaptic LTP is unaffected at parallel fiber-Purkinje cell synapses in the cerebellum of alphaCaMKII(-/-) mice. In contrast, a long-term...

Introduction: It has been demonstrated that cholecystokinin sulfated octapeptide (CCK-8s) can affect synaptic transmission in the hippocampus. Because one of the major experimental models to understand the events happening in synaptic plasticity is To Study the long-term potentiation (LTP), we decided to investigate the effect of concomitant administration of CCK-8s and tetanic stimulation of S...

Introduction: The lack of social communication is associated with the primary risk of proper brain functions. It is reported that crocin helps relieve this problem. The present study examined the protective effect of two doses of crocin on Long-term potentiation (LTP) of hippocampal cornu ammonis 1 (CA1) area as a cellular mechanism in rats exposed to chronic social isolated stress. Methods: R...

Structural and functional interrelationships between the pre- and postsynaptic elements of a singly motor innervated crab muscle (stretcher of Hyas araneus L.) were examined using electrophysiological and electron microscopic techniques. Excitatory postsynaptic potential (EPSP) amplitude at 1 Hz was found to be inversely related to the extent of facilitation, and directly related both to the am...

Development and maintenance of whisker-specific patterns along the rodent trigeminal pathway depends on an intact sensory periphery during the sensitive/critical period in development. Barrelette cells of the brain stem trigeminal nuclei are the first set of neurons to develop whisker-specific patterns. Those in the principal sensory nucleus (PrV) relay these patterns to the ventrobasal thalamu...

The granule cells of the dentate gyrus (DG) send a strong glutamatergic projection, the mossy fibre tract, toward the hippocampal CA3 field, where it excites pyramidal cells and neighbouring inhibitory interneurons. Despite their excitatory nature, granule cells contain small amounts of GAD (glutamate decarboxylase), the main synthetic enzyme for the inhibitory transmitter GABA. Chronic tempora...

Monosynaptic and polysynaptic responses of CA3 pyramidal cells (PC) to stimulation of the dentate gyrus (DG) are normally blocked by glutamate receptor antagonists (GluRAs). However, after kindled seizures, GluRAs block the monosynaptic excitatory postsynaptic potential (EPSP) and isolate a monosynaptic inhibitory postsynaptic potential (IPSP), suggesting that mossy fibers release GABA. However...