» Articles » PMID: 28913170

Comparison of Tissue Processing Methods for Microvascular Visualization in Axolotls

Overview
Journal MethodsX
Specialty Pathology
Date 2017 Sep 16
PMID 28913170
Authors
Affiliations
Soon will be listed here.
Abstract

The vascular system, the pipeline for oxygen and nutrient delivery to tissues, is essential for vertebrate development, growth, injury repair, and regeneration. With their capacity to regenerate entire appendages throughout their lifespan, axolotls are an unparalleled model for vertebrate regeneration, but they lack many of the molecular tools that facilitate vascular imaging in other animal models. The determination of vascular metrics requires high quality image data for the discrimination of vessels from background tissue. Quantification of the vasculature using perfused, cleared specimens is well-established in mammalian systems, but has not been widely employed in amphibians. The objective of this study was to optimize tissue preparation methods for the visualization of the microvascular network in axolotls, providing a basis for the quantification of regenerative angiogenesis. To accomplish this aim, we performed intracardiac perfusion of pigment-based contrast agents and evaluated aqueous and non-aqueous clearing techniques. The methods were verified by comparing the quality of the vascular images and the observable vascular density across treatment groups. Simple and inexpensive, these tissue processing techniques will be of use in studies assessing vascular growth and remodeling within the context of regeneration. Advantages of this method include: •Higher contrast of the vasculature within the 3D context of the surrounding tissue •Enhanced detection of microvasculature facilitating vascular quantification •Compatibility with other labeling techniques.

References
1.
Hasan M, Herz J, Hermann D, Doeppner T . Intravascular perfusion of carbon black ink allows reliable visualization of cerebral vessels. J Vis Exp. 2013; (71). PMC: 3582667. DOI: 10.3791/4374. View

2.
Azaripour A, Lagerweij T, Scharfbillig C, Jadczak A, Willershausen B, van Noorden C . A survey of clearing techniques for 3D imaging of tissues with special reference to connective tissue. Prog Histochem Cytochem. 2016; 51(2):9-23. DOI: 10.1016/j.proghi.2016.04.001. View

3.
Thisse C, Thisse B . High-resolution in situ hybridization to whole-mount zebrafish embryos. Nat Protoc. 2008; 3(1):59-69. DOI: 10.1038/nprot.2007.514. View

4.
Masson G, Guillette Jr L . Changes in oviducal vascularity during the reproductive cycle of three oviparous lizards (Eumeces obsoletus, Sceloporus undulatus and Crotaphytus collaris). J Reprod Fertil. 1987; 80(2):361-71. DOI: 10.1530/jrf.0.0800361. View

5.
Cole M, Crawford D, Puffer H, WARNER N . Interrelationship between PO2, morphology and perfusion in rat mammary adenocarcinoma (AD) using combined in vivo microcathode/India ink injection/freeze substitution techniques. Adv Exp Med Biol. 1983; 159:383-9. DOI: 10.1007/978-1-4684-7790-0_33. View