The role of MRI in applying the 3Rs to non-human primate neuroscience

Magnetic resonance imaging is playing a significant role in applying the 3Rs to neuroscience studies using non-human primates. MRI scans are contributing to refinement by enhancing the selection and assignment of animals, guiding the manufacture of custom-fitted recording and head fixation devices, and assisting with the diagnosis of health issues and their treatment. MRI is also being used to better understand the impact of neuroscience procedures on the welfare of NHPs. MRI has helped to optimise NHP use and make greater scientific progress than would otherwise be made using larger numbers of animals. Whilst human fMRI studies have replaced some NHP studies, their potential to directly replace NHP electrophysiology is limited at present. Given the considerable advantages of MRI for electrophysiology experiments, including improved welfare of NHPs, consideration should be given to focusing NHP electrophysiology laboratories around MRI facilities. Greater sharing of MRI data sets, and improvements in MRI contrast and resolution, are expected to further advance the 3Rs in the future.

Epilepsy in nonhuman primates

OBJECTIVES

Nonhuman primates (NHPs) are model organisms for understanding the pathophysiology and treatment of epilepsy in humans, while data from human patients informs the diagnosis and treatment of NHP with seizures and epilepsy. We reviewed the literature and surveyed veterinarians at zoos and NHP research centers to (a) better define the range of seizures and epilepsy in NHP, (b) understand how NHPs can inform our knowledge of the pathophysiology and treatment of epilepsy in humans, and (c) identify gaps of knowledge and develop more effective guidelines to treat seizures and epilepsy in NHP.

METHODS

We searched PrimateLit, PubMed, and Google Scholar for studies on experimental models of epilepsy in NHPs and on naturally occurring seizures and epilepsy in NHPs in captivity. In addition, we created a survey to assess methods to diagnose and treat epilepsy in NHPs. This survey was sent to 41 veterinarians at major international zoos and research facilities with NHP populations to study seizure phenomenology, diagnostic criteria for seizures and epilepsy, etiology, and antiseizure therapies in NHPs.

RESULTS

We summarize the data from experimental and natural models of epilepsy in NHPs and case reports of epilepsy of unknown origin in captive primates. In addition, we present survey data collected from veterinarians at eight zoos and one research facility. Experimental data from NHP epilepsy models is abundant, whereas data from primates who develop epilepsy in the wild or in zoos is very limited, constraining our ability to advance evidence-based medicine.

SIGNIFICANCE

Characterization of seizure or epilepsy models in NHPs will provide insights into mechanisms and new therapies that cannot be addressed by other animal models. NHP research will better inform species-specific diagnoses and outcomes.