Repeated electrical stimulations as a tool to evoke temporal summation of nociceptive inputs in healthy, non-medicated experimental sheep.

Rohrbach, Helene; Andersen, Ole K; Zeiter, Stephan; Wieling, Ronald; Spadavecchia, Claudia (2015). Repeated electrical stimulations as a tool to evoke temporal summation of nociceptive inputs in healthy, non-medicated experimental sheep. Physiology & behavior, 142, pp. 85-89. Elsevier 10.1016/j.physbeh.2015.02.008

[img]
Preview
Text
NWRrep stim for BORIS.pdf - Accepted Version
Available under License Publisher holds Copyright.

Download (367kB) | Preview
[img] Text
1-s2.0-S0031938415000724-main.pdf__tid=35ee9cde-b911-11e4-bb40-00000aab0f6b&acdnat=1424444609_79672cb243fc650c59c942a48cd1c81e - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (438kB) | Request a copy

The nociceptive withdrawal reflex (NWR) model is used in animal pain research to quantify nociception. The aim of this study was to evaluate the NWR evoked by repeated stimulations in healthy, non-medicated standing sheep. Repeated electrical stimulations were applied at 5Hz for 2s to the digital nerves of the right thoracic and the pelvic limbs of 25 standing sheep. The stimulation intensities applied were fractions (0.5, 0.6, 0.7, 0.8, 0.9 and 1) of the individual previously determined nociceptive threshold (It) after single stimulation. Surface-electromyographic activity (EMG) was recorded from the deltoid, the femoral biceps or the peroneus tertius muscles. The repeated stimulation threshold (RS It) was reached if at least one stimulus in the train was followed by a reflex with a minimal root-mean-square-amplitude (RMSA) of 20μV. The behavioural reaction following each series of stimulations was scored on a scale from 0 (no reaction) to 5 (vigorous whole-body reaction). For the deltoid muscle, RS It was 2.3mA (1.6-3mA) with a reaction score of 2 (1-2) and at a fraction of 0.6 (0.5-0.8)×It. For the biceps femoris muscle, RS It was 2.9mA (2.6-4mA) with a reaction score of 1 (1-2) at a fraction of and 0.55 (0.4-0.7)×It while for the peroneus tertius muscle RS It was 3mA (2.8-3.5mA) with a reaction score of 1 (1-2) and at a fraction of 0.8 (0.8-0.95)×It. Both, RMSA and reaction scores increased significantly with increasing stimulation intensities in all muscles (p<0.001). The repeated application of electrical stimuli led to temporal summation of nociceptive inputs and therefore a reduction of the stimulus intensity evoking a withdrawal reaction in healthy, standing sheep. Data achieved in this study can now serve as reference for further clinical or experimental applications of the model in this species.

Item Type:

Journal Article (Original Article)

Division/Institute:

05 Veterinary Medicine > Research Foci > NeuroCenter
05 Veterinary Medicine > Department of Clinical Veterinary Medicine (DKV)
05 Veterinary Medicine > Department of Clinical Veterinary Medicine (DKV) > DKV - Anaesthesiology

Graduate School:

Graduate School for Cellular and Biomedical Sciences (GCB)

UniBE Contributor:

Rohrbach, Helene and Spadavecchia, Claudia

Subjects:

600 Technology > 610 Medicine & health
600 Technology > 630 Agriculture

ISSN:

0031-9384

Publisher:

Elsevier

Language:

English

Submitter:

Helene Rohrbach Rüegsegger

Date Deposited:

26 Feb 2015 15:29

Last Modified:

09 Sep 2017 08:44

Publisher DOI:

10.1016/j.physbeh.2015.02.008

PubMed ID:

25659734

Uncontrolled Keywords:

Electromyogram, Nociceptive withdrawal reflex, Repeated stimulations, Sheep

BORIS DOI:

10.7892/boris.63621

URI:

https://boris.unibe.ch/id/eprint/63621

Actions (login required)

Edit item Edit item
Provide Feedback