Decerebrate mouse model for studies of the spinal cord circuits

ABSTRACT The adult decerebrate mouse model (a mouse with the cerebrum removed) enables the study of sensory-motor integration and motor output from the spinal cord for several hours without

compromising these functions with anesthesia. For example, the decerebrate mouse is ideal for examining locomotor behavior using intracellular recording approaches, which would not be

possible using current anesthetized preparations. This protocol describes the steps required to achieve a low-blood-loss decerebration in the mouse and approaches for recording signals from

spinal cord neurons with a focus on motoneurons. The protocol also describes an example application for the protocol: the evocation of spontaneous and actively driven stepping, including

optimization of these behaviors in decerebrate mice. The time taken to prepare the animal and perform a decerebration takes ∼2 h, and the mice are viable for up to 3–8 h, which is ample time

to perform most short-term procedures. These protocols can be modified for those interested in cardiovascular or respiratory function in addition to motor function and can be performed by

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FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS DISENGAGING SPINAL AFFERENT NERVE COMMUNICATION WITH THE BRAIN IN LIVE MICE Article Open access 14 September 2022

DECONSTRUCTING THE MODULAR ORGANIZATION AND REAL-TIME DYNAMICS OF MAMMALIAN SPINAL LOCOMOTOR NETWORKS Article Open access 16 February 2023 LONG-TERM OPTICAL IMAGING OF THE SPINAL CORD IN

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work was supported by Natural Sciences and Engineering Research Council grants to P.J.W. M.M. received funds from NIH NINDS R01NS077863. C.F.M. received funds from an EU FP7 Marie Curie

Fellowship and project grants from the Lundbeck Foundation. C.F.M. acknowledges the technical assistance of L. Grøhndahl of the Meehan laboratory, the assistance of A. Hedegaard of the

Meehan laboratory for the voltage clamp experiments, and advice regarding the voltage clamp and the voltage clamp external gain instrument from C.J. Heckman (Northwestern University). K.A.M.

received a studentship from the Branch Out Neurological Foundation and the Hotchkiss Brain Institute. P.J.W. and K.A.M. acknowledge the technical assistance of A. Krajacic of the Whelan

laboratory. AUTHOR INFORMATION Author notes * Claire F Meehan and Kyle A Mayr: These authors contributed equally to this work. AUTHORS AND AFFILIATIONS * Centre for Neuroscience, University

of Copenhagen, Copenhagen, Denmark Claire F Meehan * Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Alberta, Canada Kyle A Mayr & Patrick J

Whelan * CNRS UMR 8119, Université Paris Descartes, Paris, France Marin Manuel * Department of Biology, University of Hawaii at Hilo, Hilo, Hawaii, USA Stan T Nakanishi Authors * Claire F

Meehan View author publications You can also search for this author inPubMed Google Scholar * Kyle A Mayr View author publications You can also search for this author inPubMed Google Scholar

* Marin Manuel View author publications You can also search for this author inPubMed Google Scholar * Stan T Nakanishi View author publications You can also search for this author inPubMed 

Google Scholar * Patrick J Whelan View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS C.F.M., K.A.M., M.M., and S.T.N. performed the

experiments, analyzed the data, and prepared figures. P.J.W. wrote the paper and edited figures. C.F.M., K.A.M., M.M., S.T.N., and P.J.W. conceived of the experiments. C.F.M., K.A.M.,

S.T.N., M.M., and P.J.W. edited the manuscript. CORRESPONDING AUTHOR Correspondence to Patrick J Whelan. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing financial

interests. INTEGRATED SUPPLEMENTARY INFORMATION SUPPLEMENTARY FIGURE 1 INTRAMUSCULAR HOOK ELECTRODE FOR RECORDING ELECTROMYOGRAM ACTIVITY WITHIN MUSCLES (A) Rounded and sharpened curved

spatula used for decerebration. (B) Custom made leg holder used to easily make a mineral oil bath for the hindlimb muscles and nerves. (C) One completed intramuscular EMG hook electrode

using 3 stranded Teflon coated wire (A-M systems, cat No.793400) run through the lumen of a 23-gauge needle (B-D precisionGlide IM, cat No.305145). (D) Stripped 2-3 mm of Teflon coating from

the end of the stainless steel wire. (E) 180o bend backwards, creating a hook. (F) Stainless steel wire hook pulled backwards to rest in the lowest part of the bevel of the lumen. A refers

to Step 28 of procedure, b refers to Step 22. C-F refers to Step 32B. SUPPLEMENTARY FIGURE 2 INCREASE IN EMG TONE INDICATING A BOUT OF LOCOMOTION. Increase in the amplitude of flexor and

extensor EMG (tibialis anterior and gastrocnemius respectively), in the decerebrate preparation, indicating that a locomotor bout was imminent and that the treadmill should be turned on.

Tibialis Anterior (TA), Gastrocnemius (Gast). All experiments should be performed in accordance with relevant guidelines and regulations. Local ethics committees have approved all

procedures. SUPPLEMENTARY INFORMATION SUPPLEMENTARY FIGURES AND TEXT Supplementary Figures 1 and 2. (PDF 352 kb) SUPPLEMENTARY VIDEO 1. STEPPING BEHAVIOR OF A DECEREBRATE MOUSE OVER A WHEEL.

This video shows expected decerebrate walking activity and illustrates the outcome of intrathecal application of 5-HT. (MP4 5164 kb) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT

THIS ARTICLE CITE THIS ARTICLE Meehan, C., Mayr, K., Manuel, M. _et al._ Decerebrate mouse model for studies of the spinal cord circuits. _Nat Protoc_ 12, 732–747 (2017).

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