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Jørgensen LM, Baandrup AO, Mandeville J, Glud AN, Sørensen JCH, Weikop P, Jespersen B, Hansen AE, Thomsen C, Knudsen GM. An fMRI-compatible system for targeted electrical stimulation. J Neurosci Methods 2022; 378:109659. [PMID: 35772608 DOI: 10.1016/j.jneumeth.2022.109659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 06/19/2022] [Accepted: 06/24/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND Neuromodulation is a rapidly expanding therapeutic option considered within neuropsychiatry, pain and rehabilitation therapy. Combining electrostimulation with feedback from fMRI can provide information about the mechanisms underlying the therapeutic effects, but so far, such studies have been hampered by the lack of technology to conduct safe and accurate experiments. Here we present a system for fMRI compatible electrical stimulation, and the first proof-of-concept neuroimaging data with deep brain stimulation (DBS) in pigs obtained with the device. NEW METHOD The system consists of two modules, placed in the control and scanner room, connected by optical fiber. The system also connects to the MRI scanner to timely initiate the stimulation sequence at start of scan. We evaluated the system in four pigs with DBS in the subthalamic nucleus (STN) while we acquired BOLD responses in the STN and neocortex. RESULTS We found that the system delivered robust electrical stimuli to the implanted electrode in sync with the preprogrammed fMRI sequence. All pigs displayed a DBS-STN induced neocortical BOLD response, but none in the STN. COMPARISONS WITH EXISTING METHOD The system solves three major problems related to electric stimuli and fMRI examinations, namely preventing distortion of the fMRI signal, enabling communication that synchronize the experimental conditions, and surmounting the safety hazards caused by interference with the MRI scanner. CONCLUSIONS The fMRI compatible electrical stimulator circumvents previous problems related to electroceuticals and fMRI. The system allows flexible modifications for fMRI designs and stimulation parameters, and can be customized to electroceutical applications beyond DBS.
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Affiliation(s)
- Louise Møller Jørgensen
- Neurobiology Research Unit, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Inge Lehmannsvej 6-8, 2100 Copenhagen, Denmark; Copenhagen Spine Research Unit, Center for Rheumatology and Spine Diseases, Copenhagen University Hospital - Rigshospitalet, Valdemar Hansens Vej 13-17, 2600 Glostrup, Denmark; Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 2, 2200 Copenhagen, Denmark.
| | - Anders Ohlhues Baandrup
- Research Center for Advanced Imaging, Copenhagen University Hospital - Roskilde, Sygehusvej 6, 4000 Roskilde, Denmark
| | - Joseph Mandeville
- The Martinos Center, Harvard University, Massachusetts General Hospital, 149 13(th) street, Boston, MA 02129, USA
| | - Andreas Nørgaard Glud
- Department of Neurosurgery, CENSE-group, Aarhus University Hospital - Skejby, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark
| | - Jens Christian Hedemann Sørensen
- Department of Neurosurgery, CENSE-group, Aarhus University Hospital - Skejby, Palle Juul-Jensens Boulevard 165, 8200 Aarhus N, Denmark
| | - Pia Weikop
- Center for Basic and Translational Neuroscience, Nedergaard Laboratory, Division of Glial Disease and Therapeutics, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen N, Denmark
| | - Bo Jespersen
- Department of Neurosurgery, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark
| | - Adam Espe Hansen
- Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 2, 2200 Copenhagen, Denmark; Department of Radiology, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark; Department of Clinical Physiology, Nuclear Medicine & PET, Copenhagen University Hospital - Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark
| | - Carsten Thomsen
- Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 2, 2200 Copenhagen, Denmark; Research Center for Advanced Imaging, Copenhagen University Hospital - Roskilde, Sygehusvej 6, 4000 Roskilde, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Inge Lehmannsvej 6-8, 2100 Copenhagen, Denmark; Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 2, 2200 Copenhagen, Denmark
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Steinmüller JB, Bjarkam CR, Orlowski D, Sørensen JCH, Glud AN. Anterograde Tracing From the Göttingen Minipig Motor and Prefrontal Cortex Displays a Topographic Subthalamic and Striatal Axonal Termination Pattern Comparable to Previous Findings in Primates. Front Neural Circuits 2021; 15:716145. [PMID: 34899195 PMCID: PMC8661455 DOI: 10.3389/fncir.2021.716145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 11/02/2021] [Indexed: 01/20/2023] Open
Abstract
Background: Deep brain stimulation (DBS) of the dorsal subthalamic nucleus (STN) is a validated neurosurgical treatment of Parkinson’s Disease (PD). To investigate the mechanism of action, including potential DBS induced neuroplasticity, we have previously used a minipig model of Parkinson’s Disease, although the basal ganglia circuitry was not elucidated in detail. Aim: To describe the cortical projections from the primary motor cortex (M1) to the basal ganglia and confirm the presence of a cortico-striatal pathway and a hyperdirect pathway to the subthalamic nucleus, respectively, which is known to exist in primates. Materials and Methods: Five female Göttingen minipigs were injected into the primary motor cortex (n = 4) and adjacent prefrontal cortex (n = 1) with the anterograde neuronal tracer, Biotinylated Dextran Amine (BDA). 4 weeks later the animals were sacrificed and the brains cryosectioned into 30 μm thick coronal sections for subsequent microscopic analysis. Results: The hyperdirect axonal connections from the primary motor cortex were seen to terminate in the dorsolateral STN, whereas the axonal projections from the prefrontal cortex terminated medially in the STN. Furthermore, striatal tracing from the motor cortex was especially prominent in the dorsolateral putamen and less so in the dorsolateral caudate nucleus. The prefrontal efferents were concentrated mainly in the caudate nucleus and to a smaller degree in the juxtacapsular dorsal putamen, but they were also found in the nucleus accumbens and ventral prefrontal cortex. Discussion: The organization of the Göttingen minipig basal ganglia circuitry is in accordance with previous descriptions in primates. The existence of a cortico-striatal and hyperdirect basal ganglia pathway in this non-primate, large animal model may accordingly permit further translational studies on STN-DBS induced neuroplasticity of major relevance for future DBS treatments.
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Affiliation(s)
- Johannes Bech Steinmüller
- CENSE, Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark.,Department of Neurosurgery, Aalborg University Hospital, Aalborg, Denmark
| | | | - Dariusz Orlowski
- CENSE, Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Jens Christian Hedemann Sørensen
- CENSE, Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Andreas Nørgaard Glud
- CENSE, Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
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Malbert CH. Open-source 3D printable frameless stereotaxic system for young and adult pigs. J Neurosci Methods 2021; 359:109222. [PMID: 34004201 DOI: 10.1016/j.jneumeth.2021.109222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Here we present an open-source solution, comprising several 3D-printable mechanical pieces and software tools, for frameless stereotaxic targeting in young and adult pigs of varying weights. NEW METHOD Localization was achieved using an IR camera and CT imaging. The positions of the tools were followed, after registration of the pig stereotaxic space, with a CT scan and open-source brain atlas. The system was used to target the lateral ventricle and the subthalamic nucleus (STN) in one piglet and two adult Yucatan miniature pigs, which were either normal weight or obese. RESULTS AND CONCLUSIONS Positive targeting was confirmed in the first trial for all subjects, either by radiopaque CT enhancement of the ventricle or actual recording of the STN electrophysiological signature. We conclude that open-source freely available models, easily built with low-end 3D printers, and their associated software can be effectively used for brain surgery in pigs, at a minimal cost, irrespective of the weight of the animal.
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Affiliation(s)
- Charles-Henri Malbert
- Aniscan Department, Human Nutrition, INRAE, 16 Le clos, Saint-Gilles, 35590, France.
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4
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Trovatelli M, Brizzola S, Zani DD, Castellano A, Mangili P, Riva M, Woolley M, Johnson D, Rodriguez Y Baena F, Bello L, Falini A, Secoli R. Development and in vivo assessment of a novel MRI-compatible headframe system for the ovine animal model. Int J Med Robot 2021; 17:e2257. [PMID: 33817973 DOI: 10.1002/rcs.2257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 02/26/2021] [Accepted: 03/26/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND The brain of sheep has primarily been used in neuroscience as an animal model because of its similarity to the human brain, in particular if compared to other models such as the lissencephalic rodent brain. Their brain size also makes sheep an ideal model for the development of neurosurgical techniques using conventional clinical CT/MRI scanners and stereotactic systems for neurosurgery. METHODS In this study, we present the design and validation of a new CT/MRI compatible head frame for the ovine model and software, with its assessment under two real clinical scenarios. RESULTS Ex-vivo and in vivo trial results report an average linear displacement of the ovine head frame during conventional surgical procedures of 0.81 mm for ex-vivo trials and 0.68 mm for in vivo tests, respectively. CONCLUSIONS These trial results demonstrate the robustness of the head frame system and its suitability to be employed within a real clinical setting.
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Affiliation(s)
- Marco Trovatelli
- Department of Veterinary Medicine, Universitá degli Studi di Milano, Milan, Italy
| | - Stefano Brizzola
- Department of Veterinary Medicine, Universitá degli Studi di Milano, Milan, Italy
| | - Davide Danilo Zani
- Department of Veterinary Medicine, Universitá degli Studi di Milano, Milan, Italy
| | - Antonella Castellano
- Neuroradiology Unit and C.E.R.M.A.C., Vita-Salute San Raffaele University and IRCCS Ospedale San Raffaele, Milan, Italy
| | - Paola Mangili
- Medical Physics Unit, Vita-Salute San Raffaele University and IRCCS Ospedale San Raffaele, Milan, Italy
| | - Marco Riva
- Department of Oncology and Hematology-Oncology, Universitá degli Studi di Milano, Milan, Italy
| | - Max Woolley
- Renishaw Neuro Solutions Ltd., Wotton-Under-Edge, UK
| | - Dave Johnson
- Renishaw Neuro Solutions Ltd., Wotton-Under-Edge, UK
| | - Ferdinando Rodriguez Y Baena
- The Mechatronics in Medicine Laboratory, Department of Mechanical Engineering, Imperial College London, London, UK
| | - Lorenzo Bello
- Department of Oncology and Hematology-Oncology, Universitá degli Studi di Milano, Milan, Italy
| | - Andrea Falini
- Neuroradiology Unit and C.E.R.M.A.C., Vita-Salute San Raffaele University and IRCCS Ospedale San Raffaele, Milan, Italy
| | - Riccardo Secoli
- The Mechatronics in Medicine Laboratory, Department of Mechanical Engineering, Imperial College London, London, UK
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Norris C, Lisinski J, McNeil E, VanMeter JW, VandeVord P, LaConte SM. MRI brain templates of the male Yucatan minipig. Neuroimage 2021; 235:118015. [PMID: 33798725 DOI: 10.1016/j.neuroimage.2021.118015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 03/14/2021] [Accepted: 03/17/2021] [Indexed: 10/21/2022] Open
Abstract
The pig is growing in popularity as an experimental animal because its gyrencephalic brain is similar to humans. Currently, however, there is a lack of appropriate brain templates to support functional and structural neuroimaging pipelines. The primary contribution of this work is an average volume from an iterative, non-linear registration of 70 five- to seven-month-old male Yucatan minipigs. In addition, several aspects of this study are unique, including the comparison of linear and non-linear template generation, the characterization of a large and homogeneous cohort, an analysis of effective resolution after averaging, and the evaluation of potential in-template bias as well as a comparison with a template from another minipig species using a "left-out" validation set. We found that within our highly homogeneous cohort, non-linear registration produced better templates, but only marginally so. Although our T1-weighted data were resolution limited, we preserved effective resolution across the multi-subject average, produced templates that have high gray-white matter contrast and demonstrate superior registration accuracy compared to an alternative minipig template.
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Affiliation(s)
- Carly Norris
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Jonathan Lisinski
- Fralin Biomedical Research Institute, Virginia Tech, Roanoke, VA, United States
| | - Elizabeth McNeil
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - John W VanMeter
- Neurology, Georgetown University, Washington, DC, United States
| | - Pamela VandeVord
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States; Salem VA Medical Center, Salem VA, United States
| | - Stephen M LaConte
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States; Fralin Biomedical Research Institute, Virginia Tech, Roanoke, VA, United States.
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6
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Ex vivo diffusion-weighted MRI tractography of the Göttingen minipig limbic system. Brain Struct Funct 2020; 225:1055-1071. [DOI: 10.1007/s00429-020-02058-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 03/18/2020] [Indexed: 10/24/2022]
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Towards a Göttingen minipig model of adult onset growth hormone deficiency: evaluation of stereotactic electrocoagulation method. Heliyon 2019; 5:e02892. [PMID: 31844758 PMCID: PMC6895662 DOI: 10.1016/j.heliyon.2019.e02892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/24/2019] [Accepted: 11/18/2019] [Indexed: 01/09/2023] Open
Abstract
Background Adult onset growth hormone (GH) deficiency (AGDH) is a potentially underdiagnosed condition, caused by damage to the pituitary gland. AGHD is treated with growth hormone replacement therapy. A large variety of clinical symptoms and changes in the metabolic homeostasis can be observed and quantified. New large animal models are needed for future drug development. New method In this study, we evaluate methods for a new large non-primate animal model of GH deficiency in post pubertal Göttingen Minipigs (minipig). Lesions in the pituitary gland were made by stereotaxic monopolar thermo-coagulation guided by magnetic resonance imaging (MRI), and pituitary function was evaluated using insulin tolerance test (ITT) with measurements of growth hormone secretion induced by hypoglycemia. Results Lesions were successfully applied to the pituitary gland without any damage to surrounding tissue including the hypothalamus, which was confirmed by post-operative MRI and post mortem histology. Plasma levels of GH during ITT showed no decrease in secreted levels one week after surgery compared to levels obtained before surgery. Comparison with existing methods Compared to other GH insufficiency models, eloquent brain tissue is spared. Furthermore, alternatively to rodent models, a large animal model would allow the use of human intended equipment to evaluate disease. Using the minipig avoids social, economical and ethical issues, compared with primates. Conclusion The lesions did not remove all GH production, but proof of concept is demonstrated. In addition, the ITT is presented as a safe and efficient method to diagnose GH deficiency in minipigs.
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8
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Glud AN, Jakobsen S, Landau AM, Olsen Alstrup AK, Hedemann Sørensen JC. Visualization of intrathecal delivery by PET-imaging. J Neurosci Methods 2019; 317:45-48. [DOI: 10.1016/j.jneumeth.2019.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 12/20/2022]
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9
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Orlowski D, Glud AN, Palomero-Gallagher N, Sørensen JCH, Bjarkam CR. Online histological atlas of the Göttingen minipig brain. Heliyon 2019; 5:e01363. [PMID: 30949607 PMCID: PMC6429808 DOI: 10.1016/j.heliyon.2019.e01363] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/24/2019] [Accepted: 03/13/2019] [Indexed: 02/04/2023] Open
Abstract
Background The cytoarchitecture of the Göttingen minipig telencephalon has recently been elucidated in the published article (Bjarkam et al., 2017). The aim of the current paper is to describe how such data can be presented in an online histological atlas of the Gottingen minipig brain and how this atlas was constructed. Methods Two sets of histological sections were used. One set was photographed in high resolution and labelled, the other set in low resolution (resized first set) was used for reference on the computer screen. The two sets of microphotographs enable, using the freely available JQuery Image Zoom Plugin, the subsequent construction of a simple HTML-based atlas web page with a “virtual microscope like” style, which allowed magnifying of the base image (low-resolution image) up to the maximum resolution of the high-resolution image. In addition, we describe how the established histological atlas can be accompanied by a set of similar T1-weighted MRI pictures. Results and conclusion Histological and MRI pictures are presented in atlas form on www.cense.dk/minipig_atlas/index.html. The described pipeline represent a cheap and freely available way to present histological images, in online virtual microscopic atlas form, and may thus be of general interest to anyone who would like to present histological data accordingly.
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Affiliation(s)
- Dariusz Orlowski
- Center for Experimental Neuroscience (Cense), Institute of Clinical Medicine - The Department of Neurosurgery, Aarhus University, Aarhus Universitetshospital, Palle Juul-Jensens Boulevard 165, Indgang J, Plan 1, J118-125, DK-8200 Aarhus N, Denmark
| | - Andreas N Glud
- Center for Experimental Neuroscience (Cense), Institute of Clinical Medicine - The Department of Neurosurgery, Aarhus University, Aarhus Universitetshospital, Palle Juul-Jensens Boulevard 165, Indgang J, Plan 1, J118-125, DK-8200 Aarhus N, Denmark
| | - Nicola Palomero-Gallagher
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, 52425 Jülich, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen, Aachen, Germany
| | - Jens Christian H Sørensen
- Center for Experimental Neuroscience (Cense), Institute of Clinical Medicine - The Department of Neurosurgery, Aarhus University, Aarhus Universitetshospital, Palle Juul-Jensens Boulevard 165, Indgang J, Plan 1, J118-125, DK-8200 Aarhus N, Denmark.,Department of Neurosurgery, Aarhus University Hospital, Aarhus Universitetshospital, Palle Juul-Jensens Boulevard 165, Indgang J, Plan 6, DK-8200 Aarhus N, Denmark
| | - Carsten R Bjarkam
- Department of Neurosurgery, Aalborg University Hospital, and Institute of Clinical Medicine, Aalborg University, Hobrovej 18-22, DK-9000 Aalborg, Denmark
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10
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Bech J, Glud AN, Sangill R, Petersen M, Frandsen J, Orlowski D, West MJ, Pedersen M, Sørensen JCH, Dyrby TB, Bjarkam CR. The porcine corticospinal decussation: A combined neuronal tracing and tractography study. Brain Res Bull 2018; 142:253-262. [DOI: 10.1016/j.brainresbull.2018.08.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/28/2018] [Accepted: 08/02/2018] [Indexed: 12/30/2022]
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A simple, inexpensive method for subcortical stereotactic targeting in nonhuman primates. J Neurosci Methods 2018; 305:89-97. [PMID: 29768185 DOI: 10.1016/j.jneumeth.2018.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 05/10/2018] [Accepted: 05/12/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND Many current neuroscience studies in large animal models have focused on recordings from cortical structures. While sufficient for analyzing sensorimotor systems, many processes are modulated by subcortical nuclei. Large animal models, such as nonhuman primates (NHP), provide an optimal model for studying these circuits, but the ability to target subcortical structures has been hampered by lack of a straightforward approach to targeting. NEW METHOD Here we present a method of subcortical targeting in NHP that uses MRI-compatible titanium screws as fiducials. The in vivo study used a cellular marker for histologic confirmation of accuracy. RESULTS Histologic results are presented showing a cellular stem cell marker within targeted structures, with mean errors ± standard deviations (SD) of 1.40 ± 1.19 mm in the X-axis and 0.9 ± 0.97 mm in the Z-axis. The Y-axis errors ± SD ranged from 1.5 ± 0.43 to 4.2 ± 1.72 mm. COMPARISON WITH EXISTING METHODS This method is easy and inexpensive, and requires no fabrication of equipment, keeping in mind the goal of optimizing a technique for implantation or injection into multiple interconnected areas. CONCLUSION This procedure will enable primate researchers to target deep, subcortical structures more precisely in animals of varying ages and weights.
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Pirouetting pigs: A large non-primate animal model based on unilateral 6-hydroxydopamine lesioning of the nigrostriatal pathway. Brain Res Bull 2018; 139:167-173. [PMID: 29462643 DOI: 10.1016/j.brainresbull.2018.02.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/29/2018] [Accepted: 02/04/2018] [Indexed: 12/24/2022]
Abstract
INTRODUCTION The rotating 6-hydroxydopamine (6-OHDA) rat model has long been important when developing new treatment strategies for Parkinson's disease (PD). Similar non-human primate models have been developed for translational research purposes as large animal models are required by regulatory bodies as an intermediate "phase 0" trial step. However, experimental research in non-human primates encounters several economical and regulatory issues, which may be avoided by the alternative use of pigs as a large animal model for experimental brain research. OBJECTIVE The primary aim of this study was to examine if unilateral injections of 6-OHDA into the Göttingen minipig nigrostriatal pathway would lead to dopaminergic imbalance and rotational behavior similar to the 6-OHDA unilateral symptomatic model of PD created in other species. The secondary aim was to attempt to verify the rotational behavior as a parkinsonian symptom using subthalamic deep brain stimulation (STN-DBS) to minimize the elicited rotational pattern. MATERIALS AND METHODS Using an MRI-based stereotactic procedure, ten female Göttingen minipigs were injected unilaterally with 6-OHDA in the nigrostriatal pathway. Postoperatively, an MRI was performed, and the animals were injected with amphetamine and apomorphine and observed for rotational behavior. After a survival period of three months the brains were removed and immunohistochemically stained for tyrosine hydroxylase (TH). One week before sacrifice two animals had DBS electrodes unilaterally implanted in the subthalamic nucleus and various stimulation protocols were conducted during amphetamine challenge. RESULTS As expected most animals rotated towards the side of the lesion when given amphetamine (3.5-4.0 mg/kg), whereas the predicted opposite response to apomorphine were much harder to reproduce. T1- and T2-weighted postoperative MRI could demonstrate the size and the location of the 6-OHDA injection. Postmortem TH-staining of the final two animals receiving a medial and a lateral injection of 25 μL of 6-OHDA (8 μg/μL, injection rate 5 μL/min) into the diencephalic nigrostriatal pathway showed a prominent unilateral decrease in TH-staining of the substantia nigra pars compacta, the ventral tegmental area and the nigrostriatal pathway on the lesioned side. These two animals displayed spontaneous rotational behavior toward the lesioned side for the first 2-3 days postoperatively, and this behavior could later on be reelicited by amphetamine and attenuated by ipsilateral STN-DBS. CONCLUSION Female Göttingen minipigs are susceptible to unilateral dopaminergic degeneration when properly injected unilaterally with sufficient amounts of 6-OHDA in the nigrostriatal pathway. The location of the 6-OHDA injections and thus the accuracy of the employed stereotaxy can be verified in vivo using MRI postoperatively. The injected minipigs display unilateral parkinsonism with a well-defined rotational response to amphetamine that may be ameliated by STN-DBS performed on the lesioned side. The response to apomorphine was, however, not consistent, illustrating that further work on this promising non-primate large animal model is needed, before it is fully similar to the established 6-OHDA models in other species.
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13
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Lillethorup TP, Glud AN, Alstrup AKO, Mikkelsen TW, Nielsen EH, Zaer H, Doudet DJ, Brooks DJ, Sørensen JCH, Orlowski D, Landau AM. Nigrostriatal proteasome inhibition impairs dopamine neurotransmission and motor function in minipigs. Exp Neurol 2018; 303:142-152. [PMID: 29428213 DOI: 10.1016/j.expneurol.2018.02.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 01/29/2018] [Accepted: 02/06/2018] [Indexed: 01/09/2023]
Abstract
Parkinson's disease (PD) is characterized by degeneration of dopaminergic neurons in the substantia nigra leading to slowness and stiffness of limb movement with rest tremor. Using ubiquitin proteasome system inhibitors, rodent models have shown nigrostriatal degeneration and motor impairment. We translated this model to the Göttingen minipig by administering lactacystin into the medial forebrain bundle (MFB). Minipigs underwent positron emission tomography (PET) imaging with (+)-α-[11C]dihydrotetrabenazine ([11C]DTBZ), a marker of vesicular monoamine transporter 2 availability, at baseline and three weeks after the unilateral administration of 100 μg lactacystin into the MFB. Compared to their baseline values, minipigs injected with lactacystin showed on average a 36% decrease in ipsilateral striatal binding potential corresponding to impaired presynaptic dopamine terminals. Behaviourally, minipigs displayed asymmetrical motor disability with spontaneous rotations in one of the animals. Immunoreactivity for tyrosine hydroxylase (TH) and HLA-DR-positive microglia confirmed asymmetrical reduction in nigral TH-positive neurons with an inflammatory response in the lactacystin-injected minipigs. In conclusion, direct injection of lactacystin into the MFB of minipigs provides a model of PD with reduced dopamine neurotransmission, TH-positive neuron reduction, microglial activation and behavioural deficits. This large animal model could be useful in studies of symptomatic and neuroprotective therapies with translatability to human PD.
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Affiliation(s)
- Thea P Lillethorup
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Denmark
| | - Andreas N Glud
- Center for Experimental Neuroscience (CENSE), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University, Denmark
| | - Aage K O Alstrup
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Denmark
| | - Trine W Mikkelsen
- Center for Experimental Neuroscience (CENSE), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University, Denmark
| | - Erik H Nielsen
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Denmark
| | - Hamed Zaer
- Center for Experimental Neuroscience (CENSE), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University, Denmark
| | - Doris J Doudet
- Department of Medicine/Neurology, University of British Columbia, Vancouver, BC, Canada
| | - David J Brooks
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Denmark; Division of Neuroscience, Department of Medicine, Imperial College London, UK; Division of Neuroscience, Newcastle University, UK
| | - Jens Christian H Sørensen
- Center for Experimental Neuroscience (CENSE), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University, Denmark
| | - Dariusz Orlowski
- Center for Experimental Neuroscience (CENSE), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University, Denmark
| | - Anne M Landau
- Department of Nuclear Medicine and PET Center, Institute of Clinical Medicine, Aarhus University and Hospital, Denmark; Translational Neuropsychiatry Unit, Institute of Clinical Medicine, Aarhus University, Denmark.
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14
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Glud AN, Bech J, Tvilling L, Zaer H, Orlowski D, Fitting LM, Ziedler D, Geneser M, Sangill R, Alstrup AKO, Bjarkam CR, Sørensen JCH. A fiducial skull marker for precise MRI-based stereotaxic surgery in large animal models. J Neurosci Methods 2017; 285:45-48. [DOI: 10.1016/j.jneumeth.2017.04.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/23/2017] [Accepted: 04/28/2017] [Indexed: 10/19/2022]
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15
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Bjarkam CR, Orlowski D, Tvilling L, Bech J, Glud AN, Sørensen JCH. Exposure of the Pig CNS for Histological Analysis: A Manual for Decapitation, Skull Opening, and Brain Removal. J Vis Exp 2017. [PMID: 28447999 DOI: 10.3791/55511] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Pigs have become increasingly popular in large-animal translational neuroscience research as an economically and ethically feasible substitute to non-human primates. The large brain size of the pig allows the use of conventional clinical brain imagers and the direct use and testing of neurosurgical procedures and equipment from the human clinic. Further macroscopic and histological analysis, however, requires postmortem exposure of the pig central nervous system (CNS) and subsequent brain removal. This is not an easy task, as the pig CNS is encapsulated by a thick, bony skull and spinal column. The goal of this paper and instructional video is to describe how to expose and remove the postmortem pig brain and the pituitary gland in an intact state, suitable for subsequent macroscopic and histological analysis.
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Affiliation(s)
- Carsten R Bjarkam
- Department of Neurosurgery, Clinical Institute of Medicine, Aalborg University Hospital;
| | - Dariusz Orlowski
- Center of Experimental Neuroscience (Cense), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University Hospital
| | - Laura Tvilling
- Center of Experimental Neuroscience (Cense), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University Hospital
| | - Johannes Bech
- Center of Experimental Neuroscience (Cense), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University Hospital
| | - Andreas N Glud
- Center of Experimental Neuroscience (Cense), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University Hospital
| | - Jens-Christian H Sørensen
- Center of Experimental Neuroscience (Cense), Department of Neurosurgery, Institute of Clinical Medicine, Aarhus University Hospital
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16
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Orlowski D, Michalis A, Glud AN, Korshøj AR, Fitting LM, Mikkelsen TW, Mercanzini A, Jordan A, Dransart A, Sørensen JCH. Brain Tissue Reaction to Deep Brain Stimulation-A Longitudinal Study of DBS in the Goettingen Minipig. Neuromodulation 2017; 20:417-423. [PMID: 28220987 DOI: 10.1111/ner.12576] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/21/2016] [Accepted: 12/06/2016] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The use of Deep Brain Stimulation (DBS) in treatment of various brain disorders is constantly growing; however, the number of studies of the reaction of the brain tissue toward implanted leads is still limited. Therefore, the aim of our study was to analyze the impact of DBS leads on brain tissue in a large animal model using minipigs. METHODS Twelve female animals, one control and eleven with bilaterally implanted DBS electrodes were used in our experiment. 3, 6, and 12 months after implantation the animals were sacrificed, perfused and the brains were removed. Tissue blocks containing the lead tracks were dissected, frozen, sectioned into 40 µm sections and stained using Nissl and Eosin, anti-GFAPab or Isolectin. The tissue reaction was analyzed at five levels, following from the distal lead tip, to compare tissue response in stimulated and nonstimulated areas: four segments along each level of electrodes, and the fifth level lying outside the electrode area (control area). The sections were described both qualitatively and quantitatively. Quantitative assessment of the reaction to the implanted electrode was based on the measurement of the area covered by the staining and the thickness of the glial scar. RESULTS AND CONCLUSIONS Tissue reaction was, on average, limited to distance of 500 μm from the lead track. The tissue response after 12 months was weaker than after 6 months confirming that it stabilizes over a time. There was no histological evidence that the stimulated part of the electrode triggered different tissue response than its nonstimulated part.
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Affiliation(s)
- Dariusz Orlowski
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | | | - Andreas N Glud
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Anders R Korshøj
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Lise M Fitting
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Trine W Mikkelsen
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | | | - Alain Jordan
- Aleva Neurotherapeutics SA, Lausanne, Switzerland
| | | | - Jens C H Sørensen
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
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17
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Hainsworth AH, Allan SM, Boltze J, Cunningham C, Farris C, Head E, Ihara M, Isaacs JD, Kalaria RN, Lesnik Oberstein SAMJ, Moss MB, Nitzsche B, Rosenberg GA, Rutten JW, Salkovic-Petrisic M, Troen AM. Translational models for vascular cognitive impairment: a review including larger species. BMC Med 2017; 15:16. [PMID: 28118831 PMCID: PMC5264492 DOI: 10.1186/s12916-017-0793-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 01/12/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Disease models are useful for prospective studies of pathology, identification of molecular and cellular mechanisms, pre-clinical testing of interventions, and validation of clinical biomarkers. Here, we review animal models relevant to vascular cognitive impairment (VCI). A synopsis of each model was initially presented by expert practitioners. Synopses were refined by the authors, and subsequently by the scientific committee of a recent conference (International Conference on Vascular Dementia 2015). Only peer-reviewed sources were cited. METHODS We included models that mimic VCI-related brain lesions (white matter hypoperfusion injury, focal ischaemia, cerebral amyloid angiopathy) or reproduce VCI risk factors (old age, hypertension, hyperhomocysteinemia, high-salt/high-fat diet) or reproduce genetic causes of VCI (CADASIL-causing Notch3 mutations). CONCLUSIONS We concluded that (1) translational models may reflect a VCI-relevant pathological process, while not fully replicating a human disease spectrum; (2) rodent models of VCI are limited by paucity of white matter; and (3) further translational models, and improved cognitive testing instruments, are required.
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Affiliation(s)
- Atticus H Hainsworth
- Clinical Neurosciences (J-0B) Molecular and Clinical Sciences Research Institute, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK. .,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK.
| | - Stuart M Allan
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Johannes Boltze
- Department of Translational Medicine and Cell Technology, University of Lübeck, Lübeck, Germany.,Neurovascular Research Laboratory, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Catriona Cunningham
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Chad Farris
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA.,Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Elizabeth Head
- Department of Pharmacology & Nutritional Sciences, Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Masafumi Ihara
- Department of Stroke and Cerebrovascular Diseases, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Jeremy D Isaacs
- Clinical Neurosciences (J-0B) Molecular and Clinical Sciences Research Institute, St George's University of London, Cranmer Terrace, London, SW17 0RE, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Raj N Kalaria
- Institute of Neuroscience, University of Newcastle-upon-Tyne, Newcastle-upon-Tyne, UK
| | | | - Mark B Moss
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA.,Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Björn Nitzsche
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany.,Clinic for Nuclear Medicine, University of Leipzig, Leipzig, Germany.,Institute for Anatomy, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
| | - Gary A Rosenberg
- Department of Neurology, Health Sciences Center, University of New Mexico, Albuquerque, NM, USA
| | - Julie W Rutten
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands.,Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Melita Salkovic-Petrisic
- Department of Pharmacology, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Aron M Troen
- Institute of Biochemistry Food and Nutrition Science, Hebrew University of Jerusalem, Rehovot, Israel
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18
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Meidahl AC, Orlowski D, Sørensen JCH, Bjarkam CR. The Retrograde Connections and Anatomical Segregation of the Göttingen Minipig Nucleus Accumbens. Front Neuroanat 2016; 10:117. [PMID: 27994542 PMCID: PMC5136552 DOI: 10.3389/fnana.2016.00117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 11/21/2016] [Indexed: 12/12/2022] Open
Abstract
Nucleus accumbens (NAcc) has been implicated in several psychiatric disorders such as treatment resistant depression (TRD), and obsessive-compulsive disorder (OCD), and has been an ongoing experimental target for deep brain stimulation (DBS) in both rats and humans. In order to translate basic scientific results from rodents to the human setting a large animal model is needed to thoroughly study the effect of such therapeutic interventions. The aim of the study was, accordingly, to describe the basic anatomy of the Göttingen minipig NAcc and its retrograde connections. Tracing was carried out by MRI-guided stereotactic unilateral fluorogold injections in the NAcc of Göttingen minipigs. After 2 weeks the brains were sectioned and subsequently stained with Nissl-, autometallographic (AMG) development of myelin, and DARPP-32 and calbindin immunohistochemistry. The minipig NAcc was divided in a central core and an outer medial, ventral and lateral shell. We confirmed the NAcc to be a large and well-segregated structure toward its medial, ventral and lateral borders. The fluorogold tracing revealed inputs to NAcc from the medial parts of the prefrontal cortex, BA 25 (subgenual cortex), insula bilaterally, amygdala, the CA1-region of hippocampus, entorhinal cortex, subiculum, paraventricular and anterior parts of thalamus, dorsomedial parts of hypothalamus, substantia nigra, ventral tegmental area (VTA), the retrorubral field and the dorsal and median raphe nuclei. In conclusion the Göttingen minipig NAcc is a large ventral striatal structure that can be divided into a core and shell with prominent afferent connections from several subrhinal and infra-/prelimbic brain areas.
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Affiliation(s)
- Anders C Meidahl
- Department of Neurosurgery, Department of Clinical Medicine, Faculty of Health, Center for Experimental Neuroscience, Aarhus University Hospital, Aarhus University Aarhus, Denmark
| | - Dariusz Orlowski
- Department of Neurosurgery, Department of Clinical Medicine, Faculty of Health, Center for Experimental Neuroscience, Aarhus University Hospital, Aarhus University Aarhus, Denmark
| | - Jens C H Sørensen
- Department of Neurosurgery, Department of Clinical Medicine, Faculty of Health, Center for Experimental Neuroscience, Aarhus University Hospital, Aarhus University Aarhus, Denmark
| | - Carsten R Bjarkam
- Department of Neurosurgery, Institute of Clinical Medicine, Aalborg University Hospital Aalborg, Denmark
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19
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The telencephalon of the Göttingen minipig, cytoarchitecture and cortical surface anatomy. Brain Struct Funct 2016; 222:2093-2114. [PMID: 27778106 DOI: 10.1007/s00429-016-1327-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/15/2016] [Indexed: 12/19/2022]
Abstract
During the last 20 years pigs have become increasingly popular in large animal translational neuroscience research as an economical and ethical feasible substitute to non-human primates. The anatomy of the pig telencephalon is, however, not well known. We present, accordingly, a detailed description of the surface anatomy and cytoarchitecture of the Göttingen minipig telencephalon based on macrophotos and consecutive high-power microphotographs of 15 μm thick paraffin embedded Nissl-stained coronal sections. In 1-year-old specimens the formalin perfused brain measures approximately 55 × 47 × 36 mm (length, width, height) and weighs around 69 g. The telencephalic part of the Göttingen minipig cerebrum covers a large surface area, which can be divided into a neocortical gyrencephalic part located dorsal to the rhinal fissure, and a ventral subrhinal part dominated by olfactory, amygdaloid, septal, and hippocampal structures. This part of the telencephalon is named the subrhinal lobe, and based on cytoarchitectural and sulcal anatomy, can be discerned from the remaining dorsally located neocortical perirhinal/insular, pericallosal, frontal, parietal, temporal, and occipital lobes. The inner subcortical structure of the minipig telencephalon is dominated by a prominent ventricular system and large basal ganglia, wherein the putamen and the caudate nucleus posterior and dorsally are separated into two entities by the internal capsule, whereas both structures ventrally fuse into a large accumbens nucleus. The presented anatomical data is accompanied by surface renderings and high-power macrophotographs illustrating the telencephalic sulcal pattern, and the localization of the identified lobes and cytoarchitectonic areas. Additionally, 24 representative Nissl-stained telencephalic coronal sections are presented as supplementary material in atlas form on http://www.cense.dk/minipig_atlas/index.html and referred to as S1-S24 throughout the manuscript.
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20
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Glud AN, Bjarkam CR, Azimi N, Johe K, Sorensen JC, Cunningham M. Feasibility of Three-Dimensional Placement of Human Therapeutic Stem Cells Using the Intracerebral Microinjection Instrument. Neuromodulation 2016; 19:708-716. [PMID: 27593216 DOI: 10.1111/ner.12484] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 07/07/2016] [Accepted: 07/11/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The ability to safely place viable intracerebral grafts of human-derived therapeutic stem cells in three-dimensional (3D) space was assessed in a porcine model of human stereotactic surgery using the Intracerebral Microinjection Instrument (IMI) compared to a conventional straight cannula. MATERIALS AND METHODS Two groups of healthy minipigs received injections of the human stem cell line, NSI-566, into the right hemisphere and cell suspension carrier media into the left hemisphere. Group A received all injections using a straight, 21-gauge stainless steel cannula. Group B received all injections using the IMI, whereby radial distribution of injections was achieved via angular extension of a 196-micron diameter cannula from a single overlying penetration of the guide cannula. Each animal received six 20 µL intracerebral-injections within each hemisphere: three in a radial distribution, covering a 180° arc with each injection separated by a 60° arc distance, within both frontal cortex and basal ganglia. H&E and immunocytochemistry (HuNu and GFAP) were used to identify implanted cells and to assess tissue response. RESULTS The presence of surviving cells in appropriate brain regions demonstrated that the IMI is capable of accurately delivering viable human-derived stem cells safely in a 3D array at predetermined sites within the pig brain. In addition, qualitative evaluation of the target tissue suggests efficient delivery with decreased surgical trauma. CONCLUSIONS In contrast to traditional straight cannulas, the IMI enables the delivery of multiple precise cellular injection volumes in accurate 3D arrays. In this porcine large animal model of human neurosurgery, the IMI reduced surgical time and appeared to reduce neural trauma associated with multiple penetrations that would otherwise be required using a conventional straight delivery cannula.
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Affiliation(s)
| | - Carsten Reidies Bjarkam
- Department of Neurosurgery, Institute of Clinical Medicine, Aalborg University Hospital, Aalborg, Denmark
| | - Nima Azimi
- Department of Psychiatry, Laboratory for Neural Reconstruction, McLean Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | - Miles Cunningham
- Department of Psychiatry, Laboratory for Neural Reconstruction, McLean Hospital, Harvard Medical School, Boston, MA, USA.
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21
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Sweet JA, Pace J, Girgis F, Miller JP. Computational Modeling and Neuroimaging Techniques for Targeting during Deep Brain Stimulation. Front Neuroanat 2016; 10:71. [PMID: 27445709 PMCID: PMC4927621 DOI: 10.3389/fnana.2016.00071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 06/09/2016] [Indexed: 12/15/2022] Open
Abstract
Accurate surgical localization of the varied targets for deep brain stimulation (DBS) is a process undergoing constant evolution, with increasingly sophisticated techniques to allow for highly precise targeting. However, despite the fastidious placement of electrodes into specific structures within the brain, there is increasing evidence to suggest that the clinical effects of DBS are likely due to the activation of widespread neuronal networks directly and indirectly influenced by the stimulation of a given target. Selective activation of these complex and inter-connected pathways may further improve the outcomes of currently treated diseases by targeting specific fiber tracts responsible for a particular symptom in a patient-specific manner. Moreover, the delivery of such focused stimulation may aid in the discovery of new targets for electrical stimulation to treat additional neurological, psychiatric, and even cognitive disorders. As such, advancements in surgical targeting, computational modeling, engineering designs, and neuroimaging techniques play a critical role in this process. This article reviews the progress of these applications, discussing the importance of target localization for DBS, and the role of computational modeling and novel neuroimaging in improving our understanding of the pathophysiology of diseases, and thus paving the way for improved selective target localization using DBS.
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Affiliation(s)
- Jennifer A Sweet
- Department of Neurosurgery, University Hospitals Case Medical Center, Case Western Reserve University Cleveland, OH, USA
| | - Jonathan Pace
- Department of Neurosurgery, University Hospitals Case Medical Center, Case Western Reserve University Cleveland, OH, USA
| | - Fady Girgis
- Department of Neurosurgery, University Hospitals Case Medical Center, Case Western Reserve University Cleveland, OH, USA
| | - Jonathan P Miller
- Department of Neurosurgery, University Hospitals Case Medical Center, Case Western Reserve University Cleveland, OH, USA
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22
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Da Cunha C, Boschen SL, Gómez-A A, Ross EK, Gibson WSJ, Min HK, Lee KH, Blaha CD. Toward sophisticated basal ganglia neuromodulation: Review on basal ganglia deep brain stimulation. Neurosci Biobehav Rev 2015; 58:186-210. [PMID: 25684727 DOI: 10.1016/j.neubiorev.2015.02.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 02/01/2015] [Accepted: 02/05/2015] [Indexed: 12/11/2022]
Abstract
This review presents state-of-the-art knowledge about the roles of the basal ganglia (BG) in action-selection, cognition, and motivation, and how this knowledge has been used to improve deep brain stimulation (DBS) treatment of neurological and psychiatric disorders. Such pathological conditions include Parkinson's disease, Huntington's disease, Tourette syndrome, depression, and obsessive-compulsive disorder. The first section presents evidence supporting current hypotheses of how the cortico-BG circuitry works to select motor and emotional actions, and how defects in this circuitry can cause symptoms of the BG diseases. Emphasis is given to the role of striatal dopamine on motor performance, motivated behaviors and learning of procedural memories. Next, the use of cutting-edge electrochemical techniques in animal and human studies of BG functioning under normal and disease conditions is discussed. Finally, functional neuroimaging studies are reviewed; these works have shown the relationship between cortico-BG structures activated during DBS and improvement of disease symptoms.
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Affiliation(s)
- Claudio Da Cunha
- Departamento de Farmacologia, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Suelen L Boschen
- Departamento de Farmacologia, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Alexander Gómez-A
- Departamento de Farmacologia, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Erika K Ross
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | | | - Hoon-Ki Min
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Kendall H Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Charles D Blaha
- Department of Psychology, The University of Memphis, Memphis, TN, USA.
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23
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A Simple and Inexpensive Stereotactic Guidance Frame for MRI-Guided Brain Biopsy in Canines. J Med Eng 2014; 2014:139535. [PMID: 27006928 PMCID: PMC4782635 DOI: 10.1155/2014/139535] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 04/10/2014] [Accepted: 04/13/2014] [Indexed: 11/18/2022] Open
Abstract
A magnetic resonance imaging (MRI) guided stereotactic system was developed to provide veterinarians a method to accomplish minimally invasive stereotactic brain biopsies and procedures involving the cerebrum in canines. While MR-guided procedures are prevalent for humans, they are less common in animal practices. The system was designed to minimize fabrication costs in an effort to make such procedures more accessible in the veterinary field. A frame constrained the head without the need for punctures and supported registration and guidance attachments. Location data for registration and relevant structures were selected by the clinician, and a reverse kinematic analysis program generated the settings of the stereotactic arch to guide a needle to the desired location. Phantom experiments and three cadaver trials showed an average targeting error of <3 mm using the system.
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24
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Dolezalova D, Hruska-Plochan M, Bjarkam CR, Sørensen JCH, Cunningham M, Weingarten D, Ciacci JD, Juhas S, Juhasova J, Motlik J, Hefferan MP, Hazel T, Johe K, Carromeu C, Muotri A, Bui J, Strnadel J, Marsala M. Pig models of neurodegenerative disorders: Utilization in cell replacement-based preclinical safety and efficacy studies. J Comp Neurol 2014; 522:2784-801. [DOI: 10.1002/cne.23575] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Dasa Dolezalova
- Department of Anesthesiology; University of California; San Diego La Jolla CA USA
| | | | - Carsten R. Bjarkam
- Department of Neurosurgery; Aalborg University Hospital; Aalborg Denmark
- Department of Biomedicine; Institute of Anatomy, University of Aarhus; Aarhus Denmark
| | | | - Miles Cunningham
- MRC 312, McLean Hospital, Harvard Medical School; Belmont MA 02478 USA
| | - David Weingarten
- UCSD Division of Neurosurgery; University of California; San Diego CA USA
| | - Joseph D. Ciacci
- UCSD Division of Neurosurgery; University of California; San Diego CA USA
| | - Stefan Juhas
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences; 277 21 Libechov Czech Republic
| | - Jana Juhasova
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences; 277 21 Libechov Czech Republic
| | - Jan Motlik
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences; 277 21 Libechov Czech Republic
| | | | | | | | - Cassiano Carromeu
- Department of Cellular and Molecular Medicine; University of California; San Diego CA USA
| | - Alysson Muotri
- Department of Cellular and Molecular Medicine; University of California; San Diego CA USA
| | - Jack Bui
- Department of Pathology; University of California; San Diego CA USA
| | - Jan Strnadel
- Department of Pathology; University of California; San Diego CA USA
| | - Martin Marsala
- Department of Anesthesiology; University of California; San Diego La Jolla CA USA
- Institute of Neurobiology, Slovak Academy of Sciences; Kosice Slovakia
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25
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Kim JP, Min HK, Knight EJ, Duffy PS, Abulseoud OA, Marsh MP, Kelsey K, Blaha CD, Bennet KE, Frye MA, Lee KH. Centromedian-parafascicular deep brain stimulation induces differential functional inhibition of the motor, associative, and limbic circuits in large animals. Biol Psychiatry 2013; 74:917-926. [PMID: 23993641 PMCID: PMC3910443 DOI: 10.1016/j.biopsych.2013.06.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 06/05/2013] [Accepted: 06/19/2013] [Indexed: 12/17/2022]
Abstract
BACKGROUND Deep brain stimulation (DBS) of the centromedian-parafascicular (CM-Pf) thalamic nuclei has been considered an option for treating Tourette syndrome. Using a large animal DBS model, this study was designed to explore the network effects of CM-Pf DBS. METHODS The combination of DBS and functional magnetic resonance imaging is a powerful means of tracing brain circuitry and testing the modulatory effects of electrical stimulation on a neuronal network in vivo. With a within-subjects design, we tested the proportional effects of CM and Pf DBS by manipulating current spread and varying stimulation contacts in healthy pigs (n = 5). RESULTS Our results suggests that CM-Pf DBS has an inhibitory modulating effect in areas that have been suggested as contributing to impaired sensory-motor and emotional processing. The results also help to define the differential neural circuitry effects of the CM and Pf with evidence of prominent sensorimotor/associative effects for CM DBS and prominent limbic/associative effects for Pf DBS. CONCLUSIONS Our results support the notion that stimulation of deep brain structures, such as the CM-Pf, modulates multiple networks with cortical effects. The networks affected by CM-Pf stimulation in this study reinforce the conceptualization of Tourette syndrome as a condition with psychiatric and motor symptoms and of CM-Pf DBS as a potentially effective tool for treating both types of symptoms.
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Affiliation(s)
- Joo Pyung Kim
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA, Department of Neurosurgery, CHA University, Bundang CHA Medical Center, Sungnam, Republic of Korea
| | - Hoon-Ki Min
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA, Division of Engineering, Mayo Clinic, Rochester, Minnesota, USA, Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Emily J. Knight
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Penelope S. Duffy
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Osama A. Abulseoud
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, Minnesota, USA
| | - Michael P. Marsh
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Katherine Kelsey
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Charles D. Blaha
- Department of Psychology, University of Memphis, Memphis, TN, USA
| | - Kevin E. Bennet
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA, Division of Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Mark A. Frye
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, Minnesota, USA
| | - Kendall H. Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA, Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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Saito T, Uga M, Tsuzuki D, Yokota H, Oguro K, Yamamoto T, Dan I, Watanabe E. Evoked potential mapping of the rostral region by frameless navigation system in Mexican hairless pig. J Neurosci Methods 2013; 212:100-5. [DOI: 10.1016/j.jneumeth.2012.09.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 11/26/2022]
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Ettrup K, Sørensen J, Rodell A, Alstrup A, Bjarkam C. Hypothalamic Deep Brain Stimulation Influences Autonomic and Limbic Circuitry Involved in the Regulation of Aggression and Cardiocerebrovascular Control in the Göttingen Minipig. Stereotact Funct Neurosurg 2012; 90:281-91. [DOI: 10.1159/000338087] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 02/29/2012] [Indexed: 11/19/2022]
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Hypothalamic deep brain stimulation reduces weight gain in an obesity-animal model. PLoS One 2012; 7:e30672. [PMID: 22295102 PMCID: PMC3266267 DOI: 10.1371/journal.pone.0030672] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 12/20/2011] [Indexed: 11/19/2022] Open
Abstract
Prior studies of appetite regulatory networks, primarily in rodents, have established that targeted electrical stimulation of ventromedial hypothalamus (VMH) can alter food intake patterns and metabolic homeostasis. Consideration of this method for weight modulation in humans with severe overeating disorders and morbid obesity can be further advanced by modeling procedures and assessing endpoints that can provide preclinical data on efficacy and safety. In this study we adapted human deep brain stimulation (DBS) stereotactic methods and instrumentation to demonstrate in a large animal model the modulation of weight gain with VMH-DBS. Female Göttingen minipigs were used because of their dietary habits, physiologic characteristics, and brain structures that resemble those of primates. Further, these animals become obese on extra-feeding regimens. DBS electrodes were first bilaterally implanted into the VMH of the animals (n = 8) which were then maintained on a restricted food regimen for 1 mo following the surgery. The daily amount of food was then doubled for the next 2 mo in all animals to produce obesity associated with extra calorie intake, with half of the animals (n = 4) concurrently receiving continuous low frequency (50 Hz) VMH-DBS. Adverse motoric or behavioral effects were not observed subsequent to the surgical procedure or during the DBS period. Throughout this 2 mo DBS period, all animals consumed the doubled amount of daily food. However, the animals that had received VMH-DBS showed a cumulative weight gain (6.1±0.4 kg; mean ± SEM) that was lower than the nonstimulated VMH-DBS animals (9.4±1.3 kg; p<0.05), suggestive of a DBS-associated increase in metabolic rate. These results in a porcine obesity model demonstrate the efficacy and behavioral safety of a low frequency VMH-DBS application as a potential clinical strategy for modulation of body weight.
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A surgical device for minimally invasive implantation of experimental deep brain stimulation leads in large research animals. J Neurosci Methods 2011; 200:41-6. [DOI: 10.1016/j.jneumeth.2011.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Revised: 06/03/2011] [Accepted: 06/14/2011] [Indexed: 11/19/2022]
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Ettrup KS, Glud AN, Orlowski D, Fitting LM, Meier K, Soerensen JC, Bjarkam CR, Alstrup AKO. Basic surgical techniques in the Göttingen minipig: intubation, bladder catheterization, femoral vessel catheterization, and transcardial perfusion. J Vis Exp 2011:2652. [PMID: 21730947 PMCID: PMC3197034 DOI: 10.3791/2652] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The emergence of the Göttingen minipig in research of topics such as neuroscience, toxicology, diabetes, obesity, and experimental surgery reflects the close resemblance of these animals to human anatomy and physiology (1-6).The size of the Göttingen minipig permits the use of surgical equipment and advanced imaging modalities similar to those used in humans (6-8). The aim of this instructional video is to increase the awareness on the value of minipigs in biomedical research, by demonstrating how to perform tracheal intubation, transurethral bladder catheterization, femoral artery and vein catheterization, as well as transcardial perfusion. Endotracheal Intubation should be performed whenever a minipig undergoes general anesthesia, because it maintains a patent airway, permits assisted ventilation and protects the airways from aspirates. Transurethral bladder catheterization can provide useful information about about hydration state as well as renal and cardiovascular function during long surgical procedures. Furthermore, urinary catheterization can prevent contamination of delicate medico-technical equipment and painful bladder extension which may harm the animal and unnecessarily influence the experiment due to increased vagal tone and altered physiological parameters. Arterial and venous catheterization is useful for obtaining repeated blood samples and monitoring various physiological parameters. Catheterization of femoral vessels is preferable to catheterization of the neck vessels for ease of access, when performing experiments involving frame-based stereotaxic neurosurgery and brain imaging. When performing vessel catheterization in survival studies, strict aseptic technique must be employed to avoid infections(6). Transcardial perfusion is the most effective fixation method, and yields preeminent results when preparing minipig organs for histology and histochemistry(2,9). For more information about anesthesia, surgery and experimental techniques in swine in general we refer to Swindle 2007. Supplementary information about premedication and induction of anesthesia, assisted ventilation, analgesia, pre- and postoperative care of Göttingen minipigs are available via the internet at http://www.minipigs.com(10). For extensive information about porcine anatomy we refer to Nickel et al. Vol. 1-5(11).
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Affiliation(s)
- Kaare S Ettrup
- Department of Neurosurgery, Aarhus University Hospital; Department of Neurobiology, Institute of Anatomy, Faculty of Health Sciences, Aarhus University.
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Sørensen J, Nielsen M, Rosendal F, Deding D, Ettrup K, Jensen K, Jørgensen R, Glud A, Meier K, Fitting L, Møller A, Alstrup A, Østergaard L, Bjarkam C. Development of neuromodulation treatments in a large animal model—Do neurosurgeons dream of electric pigs? PROGRESS IN BRAIN RESEARCH 2011; 194:97-103. [DOI: 10.1016/b978-0-444-53815-4.00014-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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White E, Woolley M, Bienemann A, Johnson DE, Wyatt M, Murray G, Taylor H, Gill SS. A robust MRI-compatible system to facilitate highly accurate stereotactic administration of therapeutic agents to targets within the brain of a large animal model. J Neurosci Methods 2010; 195:78-87. [PMID: 21074564 PMCID: PMC3396852 DOI: 10.1016/j.jneumeth.2010.10.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 10/06/2010] [Accepted: 10/24/2010] [Indexed: 11/21/2022]
Abstract
Achieving accurate intracranial electrode or catheter placement is critical in clinical practice in order to maximise the efficacy of deep brain stimulation and drug delivery respectively as well as to minimise side-effects. We have developed a highly accurate and robust method for MRI-guided, stereotactic delivery of catheters and electrodes to deep target structures in the brain of pigs. This study outlines the development of this equipment and animal model. Specifically this system enables reliable head immobilisation, acquisition of high-resolution MR images, precise co-registration of MRI and stereotactic spaces and overall rigidity to facilitate accurate burr hole-generation and catheter implantation. To demonstrate the utility of this system, in this study a total of twelve catheters were implanted into the putamen of six Large White Landrace pigs. All implants were accurately placed into the putamen. Target accuracy had a mean Euclidean distance of 0.623 mm (standard deviation of 0.33 mm). This method has allowed us to accurately insert fine cannulae, suitable for the administration of therapeutic agents by convection-enhanced delivery (CED), into the brain of pigs. This study provides summary evidence of a robust system for catheter implantation into the brain of a large animal model. We are currently using this stereotactic system, implantation procedure and animal model to develop catheter-based drug delivery systems that will be translated into human clinical trials, as well as to model the distribution of therapeutic agents administered by CED over large volumes of brain.
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Affiliation(s)
- E White
- Department of Neurosurgery, Frenchay Hospital, Bristol, UK
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Fjord-Larsen L, Kusk P, Tornøe J, Juliusson B, Torp M, Bjarkam CR, Nielsen MS, Handberg A, Sørensen JCH, Wahlberg LU. Long-term delivery of nerve growth factor by encapsulated cell biodelivery in the Göttingen minipig basal forebrain. Mol Ther 2010; 18:2164-72. [PMID: 20664524 DOI: 10.1038/mt.2010.154] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Nerve growth factor (NGF) prevents cholinergic degeneration in Alzheimer's disease (AD) and improves memory in AD animal models. In humans, the safe delivery of therapeutic doses of NGF is challenging. For clinical use, we have therefore developed an encapsulated cell (EC) biodelivery device, capable of local delivery of NGF. The clinical device, named NsG0202, houses an NGF-secreting cell line (NGC-0295), which is derived from a human retinal pigment epithelial (RPE) cell line, stably genetically modified to secrete NGF. Bioactivity and correct processing of NGF was confirmed in vitro. NsG0202 devices were implanted in the basal forebrain of Göttingen minipigs and the function and retrievability were evaluated after 7 weeks, 6 and 12 months. All devices were implanted and retrieved without associated complications. They were physically intact and contained a high number of viable and NGF-producing NGC-0295 cells after explantation. Increased NGF levels were detected in tissue surrounding the devices. The implants were well tolerated as determined by histopathological brain tissue analysis, blood analysis, and general health status of the pigs. The NsG0202 device represents a promising approach for treating the cognitive decline in AD patients.
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