Search results for "Postsynaptic potential"

Medullary respiratory-related neurons with axonal connections to rostral pons and their function in termination of inspiration.

1985

In urethane-anaesthetized, paralyzed and artificially ventilated rabbits, medullary respiration-related neurons (RRU) were classified according to the phase relation of their burst discharge to phrenic nerve activity. Phase-bound inspiratory (I) or expiratory (E) neurons were discriminated from phase-spanning expiratory-inspiratory (EI) or inspiratory-expiratory (IE) units. Mechanisms of termination of inspiration by electrical stimulation of rostral pontine nuclei (Nc. parabrachialis medialis; Lc. coeruleus) were examined firstly to demonstrate whether RRU receive descending excitatory and inhibitory afferents as well as ascending efferents and secondly to analyse the time course of the ne…

Inhibitory Effects of the Insecticides Allethrin, Lindane, and Jacutin-Fogetten Sublimate on Photosynthetic Electron Transport

1979

Abstract The inhibitory effects of the insecticides Allethrin, Lindane, and Jacutin-Fogetten sublimate on photosynthetic electron transport of broken chloroplasts were tested. 50 μmol l-1 Allethrin caused an inhibition of 80% of the benzoquinone and ferricyanide Hill-reactions. 39 μmol l-1 Lindane inhibited the basal, coupled and uncoupled electron transport to ferricyanide up to 35%. The precipitate formed by the sublimation of Jauctin-Fogetten containing Lindane depressed electron transport much more than pure Lindane. 50 μg ml-1 of the sublimate led to an 80% inhibition of ferricyanide Hill-reaction.

Inhibition by cellular vacuolar ATPase impairs human papillomavirus uncoating and infection.

2014

ABSTRACT Several viruses, including human papillomaviruses, depend on endosomal acidification for successful infection. Hence, the multisubunit enzyme vacuolar ATPase (V-ATPase), which is mainly responsible for endosome acidification in the cell, represents an attractive target for antiviral strategies. In the present study, we show that V-ATPase is required for human papillomavirus (HPV) infection and that uncoating/disassembly but not endocytosis is affected by V-ATPase inhibition. The infection inhibitory potencies of saliphenylhalamide, a proven V-ATPase inhibitor, and its derivatives, as well as those of other V-ATPase inhibitors, were analyzed on different HPV types in relevant cell l…

A critical role for VEGF and VEGFR2 in NMDA receptor synaptic function and fear-related behavior

2016

Vascular endothelial growth factor (VEGF) is known to be required for the action of antidepressant therapies but its impact on brain synaptic function is poorly characterized. Using a combination of electrophysiological, single-molecule imaging and conditional transgenic approaches, we identified the molecular basis of the VEGF effect on synaptic transmission and plasticity. VEGF increases the postsynaptic responses mediated by the N-methyl-D-aspartate type of glutamate receptors (GluNRs) in hippocampal neurons. This is concurrent with the formation of new synapses and with the synaptic recruitment of GluNR expressing the GluN2B subunit (GluNR-2B). VEGF induces a rapid redistribution of Glu…

Preparation of ferulic acid derivatives and evaluation of their xanthine oxidase inhibition activity.

2007

Several ferulic acid ethyl esters (3a-h) were synthesized under the Knoevengel reaction condition and they were further reduced to afford the respective allylic alcohol derivatives (4a-g). Some of them were evaluated for the xanthine oxidase (XO) inhibitory activity. Among them, 3h exhibited a significant inhibitory activity with an IC50 value of 1.35 x 10(-5) M, while the IC50 value of allopurinol used as the positive control was 1.49 x 10(-5) M. The study suggested that the higher acidity of the phenolic OH group in the ferulic acid derivatives might result in improved XO inhibitory activity.

Inhibitory effect of A10 dopaminergic neurons of the ventral tegmental area on the orienting response evoked by acoustic stimulation in the cat.

1998

Abstract The effect of bilateral electric stimulation of A10 dopaminergic neurons of the ventral tegmental area (80–300 μA, 20–50 Hz, 0.1–0.5 ms, 2 s duration) on latency and duration of the orienting response, evoked by acoustic stimuli (4500–8000 Hz, 2 s), was studied in the cat. A10 neuron stimulation, simultaneous with the acoustic one, was performed with threshold parameters inducing minimal behavioral signs (head searching movement, sniffing, increase in alertness). By means of a videoanalysis system, a statistically significant increase, both of latency and duration of the response, was observed. The possible role of dopamine was studied administrating sulpiride (20 mg/kg IP), a dopa…

2002

Previous observations have suggested a role for nitric oxide in the activity of the globus pallidus, but this functional involvement has not yet been tested in vivo. The extracellular activity of single units of the globus pallidus was recorded, and neuronal nitric oxide synthase was inhibited by systemically administering 7-nitro-indazole to a group of anaesthetised rats. Forty-five per cent of cells responded with a decrease in the firing rate. In another group of rats, the microiontophoretic administration of 3-morpholino-sydnonimin-hydrocloride (a nitric oxide donor) induced an increase in neuronal firing rate (24/28 cells), whereas the administration of Nω-nitro-L-arginine methyl ester…

Brain Nucleotides and Excitatory Processes

1971

The trivial analogy in the structure of barbiturates and pyrimidines has suggested a series of studies, which were undertaken in our Laboratory since 1961 (Bonavita et al., 1960 to investigate on the role of some free nucleotides in cerebral activity.

Xenograft rejection in marine sponges. Isolation and purification of an inhibitory aggregation factor from Geodia cydonium.

1981

In sponges there exists a graft rejection mechanism in which an inhibitory aggregation factor is involved. The inhibitory aggregation factor has been isolated from a culture medium containing dissociated cells of the sponge Geodia cydonium. Using ion-exchange and gel fractionation the factor was purified and shown to be electrophoretically pure. The factor has a molecular weight of 27000 and was characterized as a glycoprotein. The activity of the inhibitory aggregation factor was not affected by heat treatment, but treatment with trichloroacetic acid resulted in the irreversible loss of activity. The inhibitory aggregation factor affects the aggregation-factor-mediated reaggregation of dis…

Investigations Concerning the Correlation of COX-1 Inhibitory and Hydroxyl Radical Scavenging Activity

2008

The aim was to study the COX-1 inhibiting efficacy in context with hydroxyl radical scavenging properties of compounds bearing a carboxylic acid and ester function, respectively. In general, the acids are more potent radical scavengers than the corresponding esters but there is no clear correlation with their COX-1 inhibiting potencies. A feasible scavenging mechanism of carboxylic acids is discussed.