Source 1primary paper2014Journal of Neuroscience
Toolkit/hindpaw thermal withdrawal threshold assay
hindpaw thermal withdrawal threshold assay
Also known as: hindpaw thermal withdrawal thresholds
Taxonomy: Technique Branch / Method. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
Subsequent optoactivation of the LC evoked repeatable, robust, antinociceptive (+4.7°C ± 1.0, p < 0.0001) or pronociceptive (-4.4°C ± 0.7, p < 0.0001) changes in hindpaw thermal withdrawal thresholds.
Usefulness & Problems
Why this is useful
This assay measures hindpaw thermal withdrawal thresholds as a behavioral readout of nociception. In the study it was used to quantify the effects of LC optoactivation.; measuring thermal nociception changes after neural manipulation
Source:
This assay measures hindpaw thermal withdrawal thresholds as a behavioral readout of nociception. In the study it was used to quantify the effects of LC optoactivation.
Source:
measuring thermal nociception changes after neural manipulation
Problem solved
It provides a direct functional output for detecting antinociceptive or pronociceptive consequences of neural activation.; provides a functional readout of anti- or pronociceptive effects
Source:
It provides a direct functional output for detecting antinociceptive or pronociceptive consequences of neural activation.
Source:
provides a functional readout of anti- or pronociceptive effects
Problem links
provides a functional readout of anti- or pronociceptive effects
LiteratureIt provides a direct functional output for detecting antinociceptive or pronociceptive consequences of neural activation.
Source:
It provides a direct functional output for detecting antinociceptive or pronociceptive consequences of neural activation.
Published Workflows
Optoactivation of Locus Ceruleus Neurons Evokes Bidirectional Changes in Thermal Nociception in Rats
2014Objective: Test whether selective optogenetic excitation of rat locus ceruleus noradrenergic neurons is antinociceptive and determine whether functional heterogeneity within LC explains bidirectional thermal nociception effects.
Why it works: The workflow combines promoter-based viral expression of channelrhodopsin-2 in LC neurons with optical activation to causally perturb the targeted population, then uses behavioral nociception readout and post hoc anatomy to relate functional effects to transduced neuron location.
excitation of locus ceruleus noradrenergic neuronssubpopulation-specific control of thermal nociceptionoptogenetic targetinglentiviral transductionbehavioral thermal withdrawal testingpost hoc anatomical characterization
Stages
- 1.Viral targeting of LC neurons(library_build)
This stage creates the optogenetically addressable LC neuron population needed for subsequent functional testing.
Selection: Expression of channelrhodopsin-2 in rat LC neurons using a PRS promoter-driven lentiviral vector.
- 2.Functional behavioral testing after LC optoactivation(functional_characterization)
This stage tests whether excitation of the targeted LC population changes thermal nociception and quantifies the direction and magnitude of the effect.
Selection: Changes in hindpaw thermal withdrawal thresholds after LC optoactivation.
- 3.Post hoc anatomical-functional localization(secondary_characterization)
This stage explains mixed behavioral outcomes by linking antinociception to a distinct ventral LC subpopulation.
Selection: Distribution of transduced somata relative to optical fiber position and further functional analysis.
Taxonomy & Function
Primary hierarchy
Technique Branch
Method: A concrete measurement method used to characterize an engineered system.
Techniques
Functional AssayTarget processes
No target processes tagged yet.
Input: Thermal
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationoperating role: sensor
The abstract supports that the assay is performed in rats after LC transduction and optoactivation. No further protocol details are given in the provided evidence.; requires an in vivo rat behavioral nociception assay
The abstract does not indicate that it resolves circuit identity or projection specificity by itself.; the abstract supports thermal nociception readout only
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
Optoactivation of PRS promoter-targeted channelrhodopsin-2-expressing rat locus ceruleus neurons evokes repeatable, robust bidirectional changes in hindpaw thermal withdrawal thresholds.
Subsequent optoactivation of the LC evoked repeatable, robust, antinociceptive (+4.7°C ± 1.0, p < 0.0001) or pronociceptive (-4.4°C ± 0.7, p < 0.0001) changes in hindpaw thermal withdrawal thresholds.
thermal withdrawal threshold change 4.7 °Cthermal withdrawal threshold change -4.4 °C
Antinociceptive actions from locus ceruleus optoactivation were evoked from a distinct ventral subpopulation of LC neurons.
Post hoc anatomical characterization of the distribution of transduced somata referenced against the position of the optical fiber and subsequent further functional analysis showed that antinociceptive actions were evoked from a distinct, ventral subpopulation of LC neurons.
Approval Evidence
1 source1 linked approval claimfirst-pass slug hindpaw-thermal-withdrawal-threshold-assay
Subsequent optoactivation of the LC evoked repeatable, robust, antinociceptive (+4.7°C ± 1.0, p < 0.0001) or pronociceptive (-4.4°C ± 0.7, p < 0.0001) changes in hindpaw thermal withdrawal thresholds.
Source:
application resultsupports
Optoactivation of PRS promoter-targeted channelrhodopsin-2-expressing rat locus ceruleus neurons evokes repeatable, robust bidirectional changes in hindpaw thermal withdrawal thresholds.
Subsequent optoactivation of the LC evoked repeatable, robust, antinociceptive (+4.7°C ± 1.0, p < 0.0001) or pronociceptive (-4.4°C ± 0.7, p < 0.0001) changes in hindpaw thermal withdrawal thresholds.
Source:
Comparisons
Source-stated alternatives
No direct assay alternatives are named in the abstract.
Source:
No direct assay alternatives are named in the abstract.
Source-backed strengths
captured repeatable and robust bidirectional changes in this study
Source:
captured repeatable and robust bidirectional changes in this study
Compared with CRISPR/Cas-hybrid assays
hindpaw thermal withdrawal threshold assay and CRISPR/Cas-hybrid assays address a similar problem space.
Shared frame: same top-level item type; same primary input modality: thermal
Strengths here: looks easier to implement in practice.
Compared with isothermal titration calorimetry
hindpaw thermal withdrawal threshold assay and isothermal titration calorimetry address a similar problem space.
Shared frame: same top-level item type; same primary input modality: thermal
Relative tradeoffs: appears more independently replicated; looks easier to implement in practice.
Compared with next-generation sequencing
hindpaw thermal withdrawal threshold assay and next-generation sequencing address a similar problem space.
Shared frame: same top-level item type; same primary input modality: thermal
Ranked Citations
- 1.