Ugo Basile Model 37570 Hargreaves Plantar Test Apparatus

Overview

The Ugo Basile Model 37570 Hargreaves Plantar Test Apparatus is a fully integrated, touchscreen-controlled instrument engineered for the quantitative assessment of thermal nociceptive thresholds in unrestrained rodents. Based on the validated Hargreaves method (Hargreaves et al., Pain, 1988), it delivers focused radiant heat through a calibrated infrared (IR) source onto the plantar surface of the hind paw via a thermally neutral glass plate. The apparatus automatically detects paw withdrawal latency—the time interval between stimulus onset and reflexive withdrawal—providing an objective, reproducible endpoint for evaluating hyperalgesia, allodynia, and antinociceptive drug efficacy. Unlike tail-flick or hot-plate assays, this method eliminates restraint-induced stress artifacts and permits unilateral testing with intrinsic control conditions, supporting rigorous within-subject experimental designs compliant with NIH and EMA guidelines for preclinical pain research.

Key Features

• 4.3-inch capacitive touchscreen interface enabling intuitive configuration, real-time monitoring, and immediate data visualization without external computers
• Digitally adjustable IR intensity (1–99) with fine-grained control over radiant energy delivery, ensuring protocol consistency across longitudinal studies
• Automated, contactless paw withdrawal detection using synchronized IR emission and reflection sensing—minimizing observer bias and inter-rater variability
• Dedicated optical filter that blocks visible-wavelength radiation (400–700 nm), eliminating non-thermal visual cues that could confound behavioral interpretation
• Modular acrylic enclosure accommodating up to 6 adult rats or 12 adult mice; designed for rapid animal loading/unloading and unobtrusive observation
• Triple-mode operation: fully automatic latency measurement, manual scoring override (for atypical locomotor responses), and programmable cutoff timer (5–30 s) to prevent tissue damage
• Embedded error-detection circuitry that identifies false triggers (e.g., ambient IR interference or premature movement), logging diagnostic flags for auditability
• USB export functionality supporting CSV-formatted datasets compatible with statistical platforms including GraphPad Prism, R, and Python pandas

Sample Compatibility & Compliance

The Model 37570 is validated for use with Mus musculus (C57BL/6, BALB/c, CD-1) and Rattus norvegicus (Sprague-Dawley, Wistar) under standard vivarium conditions (20–24 °C, 40–60% RH, 12-h light/dark cycle). Its design adheres to principles outlined in the ARRIVE 2.0 guidelines and supports compliance with GLP requirements for pharmacological safety assessment. The absence of physical restraints, coupled with standardized stimulus geometry and temporal parameters, facilitates cross-laboratory reproducibility—a prerequisite for regulatory submissions under ICH S5(R3) and FDA Guidance for Industry on Preclinical Assessment of Analgesic Drugs. All electronic subsystems meet CE marking requirements per Directive 2014/30/EU (EMC) and 2014/35/EU (LVD).

Software & Data Management

The embedded firmware implements a deterministic real-time acquisition loop with timestamp resolution of ±10 ms. Each trial records absolute start time, IR intensity setting, measured latency, operator ID (if entered), and system status flags (e.g., “cutoff activated”, “filter misalignment warning”). Data are stored locally in non-volatile memory and exported via FAT32-formatted USB drives. No proprietary software installation is required: raw files open natively in spreadsheet applications. Audit trails—including parameter changes, session start/stop events, and calibration history—are retained for ≥180 days. While not FDA 21 CFR Part 11-compliant out-of-the-box, the system supports integration into validated laboratory information management systems (LIMS) via standardized metadata tagging and UTC-synchronized timestamps.

Applications

• Quantification of thermal hyperalgesia in inflammatory (e.g., CFA-induced) and neuropathic (e.g., SNI, CCI) rodent models
• Time-course profiling of opioid and non-opioid analgesic efficacy, including tolerance development studies
• Evaluation of TRPV1 antagonist activity and mechanistic validation of novel ion channel modulators
• Behavioral phenotyping of genetically modified mouse lines with altered nociceptor function
• Standardized endpoint measurement in contract research organization (CRO) service offerings for CNS drug discovery
• Teaching laboratories requiring robust, low-maintenance instrumentation for undergraduate neuroscience curricula

FAQ

Is calibration traceable to national standards?
Yes—optional NIST-traceable infrared radiometer calibration kits are available from Ugo Basile for periodic verification of radiant flux output (W/cm²) at the glass surface.
Can the device be used with juvenile or obese animals?
The enclosure accommodates animals weighing 10–500 g; custom glass plates and spacing inserts are offered for developmental or metabolic phenotype studies.
Does the system support automated batch testing?
While not equipped with robotic handling, the touchscreen interface enables sequential single-animal testing with preloaded protocols, reducing setup time between subjects.
What maintenance is required?
Routine cleaning of the glass plate with ethanol and inspection of the IR source window every 200 hours of operation; no user-serviceable electronics.
Is technical support available outside Europe?
Ugo Basile maintains authorized service partners in North America, Asia-Pacific, and Latin America, with remote diagnostics and on-site calibration services available under extended warranty contracts.