Effective electrical head-only stunning produces a seizure-like state followed by a period of analgesia seen in animals allowed to recover. Passing of a 1·0 A current (50 Hz, 500 V) for less than 0·2 s, through the head of a sheep does not produce a seizure-like state as evidenced by recorded electroencephalogram. Corresponding to this lack of seizure-like state, the release of the neurotransmitters glutamate and aspartate, in the brain, occurs to levels associated with arousal rather than seizure. At a duration of 0·2 s, the same stun parameters as above produce a seizure-like state and the release of glutamate and aspartate rises dramatically. The length of the seizure-like state, and the levels of release of glutamate, aspartate and a third neurotransmitter gamma amino-4-butyric acid (GABA), increased with stun duration until 4·0 s duration, where a peak in these parameters was seen. Stun durations of 2·0, 4·0, 8·0 and 12·0 s all produce similar effects. At a duration of 20 s, however, the length of the seizure-like state and the release of neurotransmitters is less than at shorter stun durations. For welfare purposes a head-only electrical stun, of 1·0 A, at a duration as low as 0·2 s produces unconsciousness and analgesia to subsequent slaughter procedures. However, maximum welfare benefits appear attainable at durations between 2·0 and 20·0 s.

Download full-text PDF

Source
http://dx.doi.org/10.1016/0309-1740(94)00043-7DOI Listing

Publication Analysis

Top Keywords

seizure-like state
24
state release
12
glutamate aspartate
12
electrical head-only
8
stun duration
8
produce seizure-like
8
release neurotransmitters
8
release glutamate
8
length seizure-like
8
stun durations
8

Similar Publications

Tumor associated epilepsy is a common and debilitating co-morbidity of brain tumors, for which inadequate treatments are available. Additionally, animal models suggest a potential link between seizures and tumor progression. Our group has previously described a mouse model of diffusely infiltrating glioma and associated chronic epilepsy.

View Article and Find Full Text PDF

Asymmetric dynamics of GABAergic system and paradoxical responses of GABAergic neurons in piriform seizures.

Epilepsia

December 2024

Shanghai Pudong Hospital, Fudan University Pudong Medical Center, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science and Institutes of Brain Science, Fudan University, Shanghai, China.

Objective: The piriform cortex (PC) plays a critical role in ictogenesis, where an excitation/inhibition imbalance contributes to epilepsy etiology. However, the epileptic dynamics of the gamma-aminobutyric acid (GABA) system and the precise role of GABAergic neurons within the PC in epilepsy remain unclear.

Methods: We combined Ca and GABA sensors to investigate the dynamics of Gad2-expressing neurons and GABA levels, and selectively manipulated GABAergic neurons in the PC through chemogenetic inhibition and caspase3-mediated apoptosis targeting Gad2 interneurons.

View Article and Find Full Text PDF

Seizures are made up of the coordinated activity of networks of neurons, suggesting that control of neurons in the pathologic circuits of epilepsy could allow for control of the disease. Optogenetics has been effective at stopping seizure-like activity in non-human disease models by increasing inhibitory tone or decreasing excitation, although this effect has not been shown in human brain tissue. Many of the genetic means for achieving channelrhodopsin expression in non-human models are not possible in humans, and vector-mediated methods are susceptible to species-specific tropism that may affect translational potential.

View Article and Find Full Text PDF
Article Synopsis
  • Temporal lobe epilepsy (TLE) is difficult to diagnose due to its varied presentations and reliance on MRIs and EEGs, which may lead to underdiagnosis.
  • Symptoms can include unusual behaviors and psychiatric issues, and treatment with antiepileptic medications should be considered even if tests appear normal.
  • A case study is presented where a patient with behavioral issues and recurrent loss of consciousness, despite normal test results, significantly improved after starting divalproex sodium, demonstrating the need for awareness of TLE indicators.
View Article and Find Full Text PDF

Anti-seizure effects of norepinephrine-induced free fatty acid release.

Cell Metab

January 2025

Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY 14642, USA; Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Copenhagen, 2200 Copenhagen, Denmark; Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen N, Denmark. Electronic address:

The brain's ability to rapidly transition between sleep, quiet wakefulness, and states of high vigilance is remarkable. Cerebral norepinephrine (NE) plays a key role in promoting wakefulness, but how does the brain avoid neuronal hyperexcitability upon arousal? Here, we show that NE exposure results in the generation of free fatty acids (FFAs) within the plasma membrane from both astrocytes and neurons. In turn, FFAs dampen excitability by differentially modulating the activity of astrocytic and neuronal Na, K, ATPase.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!