The NeuroPactor™ is an electromagnetic TBI instrument that mounts on a stereotaxic instrument to deliver precise placement of reproducible impacts to  laboratory animals. Compare to pneumatics in Brody et.al.(2007) reference below.

With the actuator mounted on a stereotaxic instrument, the NeuroPactor™ is optimized for reproducible impacts in a group of animals, yielding low variability in anatomical damage and the resulting functional damage.  Impacts may be precisely positioned and reproducible impacts may be made open head (CCI), closed head (CHI), or spinally (SCI) from any angle at a preset velocity, dwell time (time in contact before automatic withdrawal), and depth.

Alternatively, the same actuator can be mounted on the optional NeuroCHIMERA™ Table,  which has  restraint for the body but not the head.  Impact through the table from below with the animal dorsal side down and with the head free to move more closely models common types of accident injury (Namjoshi, Cheng, & McInnes et. al., 2014).

ADVANTAGES of the NEUROPACTOR™ :

ADVANTAGES of the NEUROPACTOR™ ACTUATOR:

• The wires to the piston pass through the side of the cylinder, rather than wrap around the end. This prevents accidental tightening of the wires, which will prevent full retraction of the piston and attenuate its impact, possibly without notice by the experimenter.
• The set of 5 impact tips (1, 1.5, 2, 3, 5 mm) that are included screw tightly into the piston end, and will not work loose after repeated impacts. The piston end has a thread arrangement designed to prevent vibration from loosening fasteners.
• Each impact tip has a mass of 6.05 grams.  Remaining moving parts have a mass of 54 grams.  Momentum or Joules can be calculated.
• Piston will not rotate to strain wires as probes are being screwed in.
• Piston material resists swelling due to either temperature or humidity.  The piston will not lock against the cylinder interior.   Even prolonged incorrect switch position will not cause lockup.
• The piston fits snugly in the cylinder, to reduce wobble.
• Impact velocity can be set from 1.0 to 6 meters/sec.
• Contact sensor enables objective measure of zero point.
• May be mounted on common makes of stereotaxic instruments, or the Neuropactor™ CHIMERA table, to meet the experiments goals.

ADVANTAGES of the NEUROPACTOR™ CONTROL BOX:

• Since heat is no longer a problem in the actuator, additional voltage has been added to ensure the tip will always retract when it is supposed to. It should not affect operation if the switch is left in “Retract” or “Extend” for long periods.  Just for energy efficiency, it is still good practice to leave it in the central neutral position, but you will not incur any operational penalty if a student forgets.
• The Controller is calibrated to achieve a factory standard impact for the given actuator. Calibration does not shift over time, there is no need for periodic recalibration.  Any change of actuator does require factory recalibration of the controller.
• Contact Sensor provides an objective definition of where contact surface is.  Without it, different users tend to select different definitions of where the first contact depth is.

OPERATION:

Velocity is preset over a range of 1.0- 6.0 meters/second with a large rotary knob, and  is displayed in advance on a large digital display, for any application.

Dwell time, the time the tip remains in contact with the head before automatic withdrawal, used with CCI and CHI, may be preset between 0.1 and 9.9 sec.  For CHIMERA it is set to zero.

Depth of penetration is set by operating the DV drive on the stereotaxic instrument to lower the actuator, with tip extended, to just contact the head, as detected by the contact sensor, then retract the tip.  Lower the actuator with the stereotaxic instrument by the amount the tip should be allowed to travel past the impact point, and the instrument is ready to fire an impact.

The Neuropactor™ comes with a set of 5 interchangeable impact tip head sizes (1, 1.5, 2, 3, and 5 mm).  Special threads are used that do not work loose with repeated impacts.  The coil does not rotate as tips are installed or removed.  Custom tips can be made, contact us to discuss your needs.

Included:

• Actuator with cable
• Controller
• Cable for contact sensor
• Set of 5 impact tips (1, 1.5, 2, 3, & 5 mm)
• Operators Manual

Citations:

Device validation and comparison for CCI

Brody, David L., Christine Mac Donald, Chad C. Kessens, Carla Yuede, Maia Parsadanian, Mike Spinner, Eddie Kim, Katherine E. Schwetye,
David M. Holtzman, and Philip V. Bayly. “Electromagnetic controlled cortical impact device for precise, graded experimental traumatic brain
injury.” Journal of Neurotrauma 24, no. 4 (2007): 657-673.

For CCI

Ismael, Saifudeen, Sanaz Nasoohi, and Tauheed Ishrat. “MCC950, the selective inhibitor of nucleotide oligomerization domain-like receptor protein-3 inflammasome, protects mice against traumatic brain injury.”
Journal of neurotrauma 35, no. 11 (2018): 1294-1303.

Moghadas, Babak, Vimala N. Bharadwaj, John P. Tobey, Yanqing Tian, Sarah E. Stabenfeldt, and Vikram D. Kodibagkar.
“GdDO3NI Enhanced Magnetic Resonance Imaging Allows Imaging of Hypoxia After Brain Injury.”
Journal of Magnetic Resonance Imaging 55, no. 4 (2022): 1161-1168.

Vonder Haar, Cole, Frederick CW Lam, Wendy K. Adams, Lara-Kirstie Riparip, Sukhbir Kaur, Michael Muthukrishna, Susanna Rosi, and Catharine A. Winstanley.
“Frontal traumatic brain injury in rats causes long-lasting impairments in impulse control that are differentially sensitive to pharmacotherapeutics and
associated with chronic neuroinflammation.”
ACS chemical neuroscience 7, no. 11 (2016): 1531-1542.

Anderson, Gail D., Todd C. Peterson, Cole Vonder Haar, Fred M. Farin, Theo K. Bammler, James W. MacDonald, Eric D. Kantor, and Michael R. Hoane.
“Effect of traumatic brain injury, erythropoietin, and anakinra on hepatic metabolizing enzymes and transporters in an experimental rat model.”
The AAPS journal 17, no. 5 (2015): 1255-1267.

For SCI

Wanru Duan, Qian Huang, Zhiyong Chen, Srinivasa N Raja, Fei Yang, Yun Guan. Comparisons of motor and sensory abnormalities after lumbar and thoracic contusion spinal cord injury in male rats.  Neuroscience Letters 708: 2019

Yu, Shukui, Shenglian Yao, Yujun Wen, Ying Wang, Hao Wang, and Qunyuan Xu.
“Angiogenic microspheres promote neural regeneration and motor function recovery after spinal cord injury in rats.”
Scientific reports 6, no. 1 (2016): 1-13.

Cooney, Sean J., Sara L. Bermudez-Sabogal, and Kimberly R. Byrnes.
“Cellular and temporal expression of NADPH oxidase (NOX) isotypes after brain injury.”
Journal of neuroinflammation 10, no. 1 (2013): 1-13.

For CHI

Hylin, Michael & Orsi, Sara & Rozas, Natalia & Hill, Julia & Zhao, Jing & Redell, John & Moore, Anthony & Dash, Pramod. (2013).
Repeated Mild Closed Head Injury Impairs Short-Term Visuospatial Memory and Complex Learning.
Journal of neurotrauma. 30. 10.1089/neu.2012.2717.

Yoshitsugu Shitaka, PhD, Hien T. Tran, BA, Rachel E. Bennett, BA, Laura Sanchez, Marilyn A. Levy, BA, Krikor Dikranian, PhD,
David L. Brody, MD, PhD, Repetitive Closed-Skull Traumatic Brain Injury in Mice Causes Persistent Multifocal Axonal Injury and Microglial
Reactivity, Journal of Neuropathology & Experimental Neurology, Volume 70, Issue 7, July 2011, Pages 551–567.

Jamnia, Naseem, Janice H. Urban, Grace E. Stutzmann, Sarah G. Chiren, Emily Reisenbigler, Robert Marr, Daniel A. Peterson, and
Dorothy A. Kozlowski. “A clinically relevant closed-head model of single and repeat concussive injury in the adult rat using a
controlled cortical impact device.” Journal of neurotrauma 34, no. 7 (2017): 1351-1363.

CHI Rubber tips
Meconi, Alicia, Ryan C. Wortman, David K. Wright, Katie J. Neale, Melissa Clarkson, Sandy R. Shultz, and Brian R. Christie.
“Repeated mild traumatic brain injury can cause acute neurologic impairment without overt structural damage in juvenile rats.”
PloS one 13, no. 5 (2018): e0197187. 7mm plastic tip