Anterograde and retrograde tracing with high molecular weight biotinylated dextran amine through thalamocortical and corticothalamic pathways

Abstract

Biotinylated dextran amine (BDA) has been used for neural pathway tracing in the central nervous system for many decades, in which high molecular weight BDA appeared to be transported predominantly in the anterograde direction and less in the retrograde direction. In the current study, we reexamined the properties of neural labeling with high molecular weight BDA through a reciprocal neural pathway between thalamus and somatosensory cortex. After injection of BDA into the ventral posteromedial nucleus of thalamus (VPM) in the rat, the BDA labeling was sequentially examined on somatosensory cortex at 3, 5, 7, 10, and 14 survival days. Both of anterogradely labeled axonal terminals and retrogradely labeled neuronal cell bodies were observed simultaneously on the somatosensory cortex. With the increasing of survival times after injection, morphological changes occurred on the labeled axonal arbors and neuronal dendrites, in which the high quality of BDA labeling appeared on the tenth survival day. These results indicate that high molecular weight BDA is not only a sensitive anterograde tracer but also an excellent retrograde marker to be used for tracing through thalamocortical and corticothalamic pathways. And the detailed structure of neural labeling with BDA similar to Golgi-like resolution can be obtained at optimal survival times of animals after the injection of high molecular weight BDA.

Massively Parallel High‐Throughput Single‐Cell Patterning and Large Biomolecular Delivery in Mammalian Cells Using Light Pulses

“…Dextrans are cell impermeable hydrophilic polysaccharides that are often employed to monitor cell division, follow the movement of living cells, and evaluate the hydrodynamic characteristics of the cytoplasmic matrix. [51,52] Here, we were able to Similarly, Figure 7d-f shows dextran delivery, cell viability and merged image for 100 μm patterned area. The Calcein-AM image and merged image confirmed that cells are live after successful Dextran delivery.…”

“…Dextrans are cell impermeable hydrophilic polysaccharides that are often employed to monitor cell division, follow the movement of living cells, and evaluate the hydrodynamic characteristics of the cytoplasmic matrix. [ 51,52 ] Here, we were able to successfully deliver Tetramethylrhodamine‐labeled Dextran 3000 MW (Life Technologies) in a massively parallel manner utilizing the TMD device. The delivery efficiency for different concentration of Dextran 3000 was studied as shown in Figure S3b (Supporting Information) and was optimized at 30 µg mL −1 for further experiments.…”

In Vivo and 3D Imaging Technique(s) for Spatiotemporal Mapping of Pathological Events in Experimental Model(s) of Spinal Cord Injury

“…With the advancements, scientists have developed various imaging techniques to trace neural networks using various chemical reagents. Some include dextran amines, Cholera β-Toxin subunit, tetanus toxin, and fluorogold. − Dextran amines are lipophilic organic compounds with low toxicity and immunogenicity . These amines react with avidin–biotinylated horseradish peroxidase, followed by diaminobenzene as a substrate, and further analyzed by optical microscopy [Figure ].…”

Corrigendum: A Student's Guide to Neural Circuit Tracing

“…Despite the common perception that DAs are preferential anterograde tracers, many studies indicate bidirectional travel (Schmued et al, 1990;Fritzsch, 1993;Glover, 1995;Zhang et al, 2017), including the original description of their axonal transport by Glover et al (1986). Their retrograde capabilities have been exploited both for conventional tracing (Sivertsen et al, 2014(Sivertsen et al, , 2016Lunde et al, 2019) and for delivery of calcium-sensitive indicators for optical recording of neurons selected by axonal trajectory (O'Donovan et al, 1993;McPherson et al, 1997).…”

“…4. The direction of axonal transport is rarely exclusive, which complicates circuit analysis; the archetypal retrograde and anterograde tracers, CTb and BDA respectively, both label axons traveling in the "wrong" direction (Luppi et al, 1987;Schmued et al, 1990;Fritzsch, 1993;Glover, 1995;Angelucci et al, 1996;Noseda et al, 2010;Zhang et al, 2017). "…”