Dynamic changes of touch- and laser heat-evoked field potentials of primary somatosensory cortex in awake and pentobarbital-anesthetized rats

Shaw, Fu-Zen; Chen, Ruei-Feng; Yen, Chen‐Tung

doi:10.1016/s0006-8993(01)02686-5

Cited by 52 publications

(49 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…At this intensity, consistent with previous studies (Shaw et al 1999(Shaw et al , 2001Tsai et al 2004), short-(LEP1) and long-latency (LEP2) evoked potentials were recorded from the EEG skull electrode in the rostral parietal region. The average LEP1 and LEP2 values of the eight rats were 67 Ϯ 3 and 356 Ϯ 7 ms, respectively (Table 1).…”

Section: Acc and Smi Responses To Laser Irradiation Of The Mid-tailsupporting

confidence: 87%

“…This was for the laser-heat-evoked potential recording, because in previous studies it was shown that the laser-heat-evoked potentials from the tail stimulation can be recorded bilaterally on both sides of the SmI (Shaw et al1999(Shaw et al , 2001. The ground electrode consisted of stainless-steel screws located over the top of the cerebellum (mid-occipital bone).…”

Section: Surgical Proceduresmentioning

confidence: 99%

“…The 10.6-m wavelength infrared radiation of the CO 2 laser selectively activates nociceptive receptors and generates a pure pain sensation, which is conveyed through both myelinated A-␦ and unmyelinated C fibers to the cerebral cortex in humans (Bromm andTreede 1984, 1987). Two cortical laser-evoked potentials (LEP1 and LEP2) have been recorded from the cerebral cortex of the rat (Shaw et al 1999(Shaw et al , 2001). The conduction velocities of the peripheral fibers responsible for the activation of these LEPs have been estimated.…”

Section: Fig 6 Comparison Of Short-(arrowheads)mentioning

confidence: 99%

See 2 more Smart Citations

Comparison of Anterior Cingulate and Primary Somatosensory Neuronal Responses to Noxious Laser-Heat Stimuli in Conscious, Behaving Rats

Kuo¹,

Yen²

2005

Journal of Neurophysiology

Self Cite

View full text Add to dashboard Cite

Kuo, Chung-Chih and Chen-Tung Yen. Comparison of anterior cingulate and primary somatosensory neuronal responses to noxious laser-heat stimuli in conscious, behaving rats. J Neurophysiol 94: 1825-1836, 2005; 10.1152/jn.00294.2005. In this study, we investigated single-unit responses of the primary sensorimotor cortex (SmI) and anterior cingulate cortex (ACC) to noxious stimulation of the tail of the rat. The influences of morphine on these nociceptive responses were also compared. Multiple single-unit activities were recorded from two eight-channel microwire arrays chronically implanted in the tail region of the SmI and ACC, respectively. CO 2 laser-heat irradiation of the middle part of the tail at an intensity slightly higher than that causing a maximal tail flick response was used as a specific noxious stimulus. Examined individually, ACC neurons were less responsive than SmI neurons to laser-heat stimulus, in that only 51% of the ACC units (n ϭ 125) responded compared with 88% of the SmI units (n ϭ 74). Among these responsive ACC units, many had a very long latency and long-lasting excitatory type of response that was seldom found in the SmI. When ensemble activities were examined, laser heat evoked both short-(60 ϳ 150 ms) and long-latency (151 ϳ 600 ms) responses in the SmI and ACC. Latencies of both responses were longer in the ACC. Furthermore, a single dose of 2.5-10 mg/kg morphine intraperitoneally suppressed only the long latency response in the SmI, but significantly attenuated both responses in the ACC. These effects of morphine were completely blocked by prior treatment with the opiate receptor blocker, naloxone. These results provide further evidence suggesting that the SmI and ACC may play different roles in processing noxious information. I N T R O D U C T I O NRecent neuroimaging studies in human subjects have revealed several key forebrain areas most often activated by noxious stimulations. Among these areas are the primary somatosensory cortex (SI) and anterior cingulate cortex (ACC) (Casey et al. 1994; Coghill et al. 1994 Coghill et al. , 1999 Craig et al. 1996; Davis et al. 1995; Dorbyshire et al. 1997; Hsieh et al. 1995; Talbot et al. 1991; Vogt et al. 1996). Furthermore, studies by Rainville et al. (1997) and Hofbauer et al. (2001) showed that functional MRI (fMRI) intensities in the SI were correlated with the intensity of the noxious heat, whereas those in the ACC were better correlated with subjective unpleasantness, suggesting a differential functional role between SI and ACC.In contrast, the processing of nociceptive information in the forebrain at the cellular level is largely unclear. Neuroanatomical and neurophysiological studies have shown that pain information is processed through a complicated serial and parallel network in the forebrain (Craig 2003; Willis 1985). Electrophysiological studies of the SI have revealed nociceptive neu-

show abstract

Section: Acc and Smi Responses To Laser Irradiation Of The Mid-tailsupporting

confidence: 87%

Section: Surgical Proceduresmentioning

confidence: 99%

Section: Fig 6 Comparison Of Short-(arrowheads)mentioning

confidence: 99%

See 1 more Smart Citation

Comparison of Anterior Cingulate and Primary Somatosensory Neuronal Responses to Noxious Laser-Heat Stimuli in Conscious, Behaving Rats

Kuo¹,

Yen²

2005

Journal of Neurophysiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is known that electrical stimulation as used in the present study activates Aa-fibers involved in motor processing, Ah-fibers involved in mechanosensation, and Ay-and C-fibers [3,4,11,12]. Based on the conduction velocities (Aa: 60-70 m/s, Ah: 30-40 m/s, Ay: 4-30 m/s, and C: 0.4-1.8 m/s) [3,4,11,12] and the distance between the stimulus location and the recording site in this study (approximately 0.15-0.20 m), both Ah-and Ay-mediated responses can be found within the latency range examined in the present study. It has been shown that the Vx-SEP P15 [15] and P37 (unpublished observations, PJ Stienen) are affected by the A-opioid receptor agonist fentanyl.…”

Section: Discussionmentioning

confidence: 99%

Development of a rat model to assess the efficacy of the somatosensory-evoked potential as indicator of analgesia

Oostrom

Stienen

Bos

et al. 2005

Brain Research Protocols

View full text Add to dashboard Cite

Drug-induced changes in somatosensory-evoked potentials (SEPs) are considered to reflect an altered nociceptive state. Therefore, the SEP is proposed to be a parameter of analgesic efficacy. However, at present, SEPs have not been studied in relation to animal pain. The present study aims to develop a rat model in which this relationship can be studied based on Pavlovian fear conditioning. Therefore, rats, implanted with epidural electro-encephalogram recording electrodes, were randomly assigned to either a paired or random-control group and subjected to an aversive-to-appetitive transfer paradigm. During the aversive phase, the SEP-stimulation paradigm (5 mA square wave pulses, n = 72, of 2 ms duration each, with a stimulus frequency of 0.5 Hz; total duration 144 s) was used as the unconditioned stimulus (US), while a tone (40 s, 1500 Hz, 85 dB sound pressure level) was used as the conditioned stimulus (CS). During the appetitive phase, the CS was presented paired to the presentation of a sugar pellet. When compared to the random-control group, the paired group showed significantly more freezing behavior and significantly less reward-directed behavior in response to the CS in the appetitive phase. In addition, SEPs were not significantly affected by fear conditioning. Based on these results, we conclude that the SEP-stimulation paradigm can be successfully employed as a US in fear conditioning. In future studies, fear conditioning can be carried out under different levels of an analgesic regimen to allow the changes in SEP parameters to be compared to changes in fear-induced behavior making this model potentially useful to validate SEP parameters as indicators of analgesia. D 2005 Elsevier B.V. All rights reserved.Theme: Neural basis of behavior Topic: Learning and memory: systems and functions-animals

show abstract

“…Laser-evoked cortical responses can be classified into two groups [Danneman et al, 1994, Isseroff et al, 1982, Kalliomaki et al, 1993. The first group, mediated by Aδ-fibers, is more sensitive to pentobarbital-induced anesthesia [Shaw et al, 2001] and laser pulse energy level [Kalliomaki et al, 1993]. The second group, mediated by C-fibers, is widespread across the cortical surface and can be diminished by topical morphine application onto the lumbar spinal cord and reversed by naloxone [Kalliomaki et al, 1998].…”

Section: Introductionmentioning

confidence: 99%

CO₂ Laser Pulse-Evoked Nocifensive Behavior Mediated by C-Fibers

Shyu¹

2010

Laser Pulse Phenomena and Applications

View full text Add to dashboard Cite

Dynamic changes of touch- and laser heat-evoked field potentials of primary somatosensory cortex in awake and pentobarbital-anesthetized rats

Cited by 52 publications

References 34 publications

Comparison of Anterior Cingulate and Primary Somatosensory Neuronal Responses to Noxious Laser-Heat Stimuli in Conscious, Behaving Rats

Comparison of Anterior Cingulate and Primary Somatosensory Neuronal Responses to Noxious Laser-Heat Stimuli in Conscious, Behaving Rats

Development of a rat model to assess the efficacy of the somatosensory-evoked potential as indicator of analgesia

CO₂ Laser Pulse-Evoked Nocifensive Behavior Mediated by C-Fibers

Contact Info

Product

Resources

About