Cerebral neurons

These amino acid transmitters are predominant, accounting for most of the fast synaptic transmission in the brain. Together they occur in 70-80% of cerebral neurons. The concentration of GABA is for example up to 1000 times greater than that of other transmitters like acetylcholine or dopamine. 

The convincing evidence from the experimental work presented here supports the conclusion that EGb is effective for the treatment of dementia and cerebral insufficiency. To sum up the major characteristics of the pharmacological activities of EGb, particularly in the CNS, the following conclusions can be readied. EGb improves hypoxic tolerance and protects cerebral neurons against apoptosis-, edema- and ischemia-induced injury. In addition, EGb inhibits age-related impairment of cerebral neurotransmitters, inducting muscarinic receptors, and 2-... 

In conclusion, the distribution of H3 receptors and the effects of lesions are consistent with functional studies showing that they are inhibitory receptors not only on histaminergic nerve terminals, but also on various aminergic and non-aminergic cerebral neurons and therefore they may be involved in a large variety of functions. 

Epilepsy is a chronic neurologic disorder characterized by recurrent seizures.33 Seizures are episodes of sudden, transient disturbances in cerebral excitation that occur when a sufficient number of cerebral neurons begin to fire rapidly and in synchronized bursts.42 Depending on the type of seizure, neuronal activity may remain localized in a specific area of the brain, or it may spread to other areas of the brain. In some seizures, neurons in the motor cortex are activated, leading to skeletal muscle contraction via descending neuronal pathways. These involuntary, paroxysmal skeletal muscle contractions seen during certain seizures are referred to as convulsions. However, convulsions are not associated with all types of epilepsy, and other types of seizures are characterized by a wide variety of sensory or behavioral symptoms. 

Seizure A sudden attack of symptoms usually associated with diseases such as epilepsy. Epileptic seizures are due to the random, uncontrolled firing of a group of cerebral neurons, which results in a variety of sensory and motor manifestations. 

At high concentrations, phenytoin also inhibits the release of serotonin and norepinephrine, promotes the uptake of dopamine, and inhibits monoamine oxidase activity. The drug interacts with membrane lipids this binding might promote the stabilization of the membrane. In addition, phenytoin paradoxically causes excitation in some cerebral neurons. A reduction of calcium permeability, with inhibition of calcium influx across the cell membrane, may explain the ability of phenytoin to inhibit a variety of calcium-induced secretory processes, including release of hormones and neurotransmitters. The significance of these biochemical actions and their relationship to phenytoin s clinical activity are unclear. 

Cerebral cortex has an intrinsic oscillating field in the extracellular fluid, the EEG. It appears to originate principally in the enormously branched dendrites that characterize cerebral neurons. Measured over cellular dimensions, the EEG has a typical gradient of 50 mV/cm (20, 21), and a frequency spectrum from 1 to 100 Hz, with most energy in the band from 1 to 20 Hz. Records from intracellular microelectrodes in many but not all cerebral neurons display large slow oscillations up to 15 mV in amplitude that resemble the EEG from the same cortical region in spectral analyses. However, with an amplitude of 20-50 uV, the EEG is less than 1.0 percent of the amplitude of the intracellular neuronal waves from which it is derived, due to its attenuation in the neuronal membrane. 

Chih, C. P., Lipton, P., Roberts, E. L ). Do 7 active cerebral neurons really use lactate rather than glucose Trends Neurosci. 2001, 24 573-578. 

Coin, E. J. (1975). Long-lasting changes in cerebral neurons induced by drugs. Biological Psychiatry, 10, 227-264. 

Williams MA, Turchan J, Lu Y, Nath A, Drachman DB (2005) Protection of human cerebral neurons from neurodegenerahve insults by gene delivery of soluble tumor necrosis factor p75 receptor. Exp Brain Res 165 383—391. 

Epilepsy affects 5-10 per 1000 of the general population. It is due to sudden, excessive depolarisation of some or all cerebral neurons. This may remain localised (focal seizure) or may spread to cause a secondary generalised seizure, or affect all... 

Increased stimulations from the cerebral neurons or lack of inhibition in the spinal cord or at the skeletal muscles cause hyperexcitable neurons, resulting in increased muscle tone and spasticity. 

Epilepsy is when abnormal electric discharges from the cerebral neurons result in a loss or disturbance of... 

The time delay between sensory signaling and the subjective conscious perception of sensation which has so carefully been demonstrated by neurosurgeon Benjamin Li bet and other experimenters may also have a simpler explanation than those proposed so far. Li bet and others have shown that a pin-prick of the finger, for example, transmits a signal to the cortex of the brain via the thalamus, which arrives in a few thousandths of a second. All sensory signaling except olfaction is similarly transmitted first to the thalamus which acts as a sort of relay-station distributing the signals to the appropriate domains of the cortex. Yet conscious perception of the pin-prick can by various experimental techniques be shown to be delayed by up to a half-second, while "cerebral neuronal adequacy" is achieved. 

Park, S.T., K.T. Lim, Y.T. Chung, and S.U. Kim. 1996. Methylmercury-induced neurotoxicity in cerebral neuron culture is blocked by antioxidants and NMDA receptor antagonists. 

A single intraperitoneal administration of butylphthalide (30) (50-100 mg/kg) prolonged pentobarbital-induced sleep time in male Albino mice [287]. A similar effect was also observed after inhalation of 30 at 0.5-lmg/3L air/min [288-290]. Furthermore, in a rat chronic seizure model induced by coriaria lactone [291-295], significant damage was found in the cerebral neurons and cerebellar Purkinje cells in control animals after seizure induction, but not in rats orally pretreated with 700 mg/kg of phthalide 30. In addition, compound 30 appeared to antagonize learning and memory impairment in the same animal model. 

Pyruvate carboxylase deficiency is one of the genetic diseases grouped together under the clinical manifestations of Leigh s disease (subacute necrotizing encephalopathy). In the mild form, the patient presents early in life with delayed development and a mild-to-moderate lactic acidemia. Patients who survive are severely mentally retarded, and there is a loss of cerebral neurons. In the brain, pyruvate carboxylase is present in the astrocytes, which use TCA cycle intermediates to synthesize glutamine. This pathway is essential for neuronal survival. The major cause of the lactic acidemia is that cells dependent on pyruvate carboxylase for an anaplerotic supply of oxaloacetate cannot oxidize pyruvate in the TCA cycle (because of low oxaloacetate levels), and the liver cannot convert pyruvate to glucose (because the pyruvate carboxylase reaction is required for this pathway to occur), so the excess pyruvate is converted to lactate. 

Bernards, A. de la Monte, S.M. The Itk receptor tyrosine kinase is expressed in pre-B lymphocytes and cerebral neurons and uses a non-AUG translational initiator. EMBO J., 9, 2279-2287 (1990)... 

Seizures Finite episodes of brain dysfunction resulting from abnormal discharge of cerebral neurons... 

GABA is an inhibitory amino acid neurotransmitter of brain interneurons and other cerebral neurons. The enzyme glutamic acid decarboxylase catalyzes the synthesis of GABA from glutamate. GABA is stored in presynaptic vesicles and binds to either GABA-A or GABA-B receptors upon release. 

Epilepsy is a chronic disease in which seizures result from the abnoniial discharge of cerebral neurones. The seizures are classified empirically. 

Epilepsy is a seizure disorder where there is an abnormal electric discharge from the cerebral neurons that result in loss or disturbance of consciousness and convulsion (abnormal motor reaction). Epilepsy affects 1% of people in the United States. 

The human brain develops unevenly (Wallis, 2004). The maximum brain cell density occurs between the third and sixth month of pregnancy. During the final months before birth, a dramatic pruning of unnecessary brain cells eliminates many neurons. After birth, the number of cerebral neurons continues to decline at a slower pace. New neurons can still be created, but more are lost than gained. 

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