MRI-guided dissection of the nonhuman primate brain: A case study

Abstract

Numerous biochemical as well as electrophysiological techniques require tissue that must be retrieved very quickly following death in order to preserve the physiological integrity of the neuronal environment. Therefore, the ability to accurately predict the precise locations of brain regions of interest (ROI) and to retrieve those areas as quickly as possible following the brain harvest is critical for subsequent analyses. One way to achieve this objective is the utilization of high resolution MRI scans to guide the subsequent dissections. In the present study, individual MRI scans of the brains of rhesus and cynomolgus macaques that had chronically self-administered ethanol were employed in order to determine which blocks of dissected tissue contained specific ROIs. MRI-guided brain dissection of discrete brain regions was completely accurate in 100% of the cases. In comparison, approximately 60–70% accuracy was achieved in dissections that relied on external landmarks alone without the aid of MRI. These results clearly demonstrate that the accuracy of targeting specific brain areas can be improved with high-resolution MR imaging.

Genome-wide analysis of the nucleus accumbens identifies DNA methylation signals differentiating low/binge from heavy alcohol drinking

“…Briefly, monkeys were anesthetized with ketamine (10 mg/kg), maintained on isoflurane, and perfused with ice-cold oxygenated monkey perfusion solution [containing (in mM) 124 NaCl, 23 NaHCO 3 , 3 NaH 2 PO 4 , 5 KCl, 2 MgSO 4 , 10 d -glucose, 2 CaCl 2 ]. Brains were quickly removed and sectioned along the coronal plane using a brain matrix (Daunais et al, 2010). The block containing the NAcc was initially selected by each individual’s MRI images and verified using visible landmarks.…”

Increased presynaptic regulation of dopamine neurotransmission in the nucleus accumbens core following chronic ethanol self-administration in female macaques

“…A craniotomy was performed followed by perfusion with chilled artificial cerebral spinal fluid. Once the perfusion was complete (within 4 minutes) the brain was immediately removed, placed into a brain block and dissected into 4-mm coronal sections, as described previously (Daunais et al, 2010). A section containing the nucleus accumbens was removed and placed into oxygenated artificial CSF.…”

3D structure tensor analysis of light microscopy data for validating diffusion MRI

“…Following cerebral perfusion fixation with 4% paraformaldehyde, the brain was immersed in 4% paraformaldehyde for 24 hours and subsequently transferred to phosphate-buffered saline (PBS). The brain was sectioned into 5 mm-thick coronal blocks as described in (Daunais et al, 2010), and the left hippocampus and associated white matter, including the alveus and inferior longitudinal fasciculus (ILF), was extracted for ex-vivo MRI and histological analyses (Fig. 1).…”