Visualizing vertebrate skeletal bone formation
Mesenchyme tissue condenses to form cartilage. The cartilage is later replaced by bone; although, there are some structures that remain permanently cartilage and do not ossify, such as the cartilage of the trachea and articular cartilage of the joints. Alcian Blue/Alizarin red staining is ideal for revealing the cartilaginous skeleton of developing embryos. The cartilaginous skeleton is stained dark blue by Alcian Blue, the bone is stained with Alizarin Red, and the other embryonic tissues are “cleared” using benzyl alcohol/benzyl benzoate (BABB). Here are some examples:
1. Alcian blue staining of a Stage 17 BAT (Carollia perspicillata) embryo. This image was taken by Lingyu Wang and Ketty Lee. http://thenode.biologists.com/tag/mouse/
2. This remarkable image shows the forming skeleton of an embryonic CHICKEN, stained to differentiate between hardened bone (in red) and the still-unossified cartilage model (in blue). http://www.vetmed.vt.edu/education/curriculum/vm8304/lab_companion/histo-path/vm8054/labs/Lab8/Examples/chickbon.htm
3. A MOUSE embryonic skeleton, with bone stained Alizarin Red and cartilage stained Alcian Blue. [Credit: Jacqueline Norrie, graduate student, Institute for Cellular and Molecular Biology] http://www.utexas.edu/know/2013/09/30/science-visualized/
4. Alcian blue staining of an advanced CORN SNAKE embryo to show the skeletal anatomy.
5. Alcian blue staining of a WHIPTAIL LIZARD..Image(s) by Andrea Wills (2007 Woods Hole Embryology Course)
6. The image shows the ventral surface of the SKATE RAJA prepared by alcian blue and alizarin red staining for cartilage and bone. (With additional staining of the ampullary canals surrounding the face.) It was taken by David Gold (University of California, Los Angeles), Lynn Kee (University of Michigan), and Meghan Morrissey (Duke University). http://thenode.biologists.com/skate-wins-cover-contest/photo/
7. 40-day old CAT fetus shows its cartilaginous skeleton stained with alcian blue. The specimen was also stained with alizarin red, which stainscalcium.
8. Lateral view, fetal HUMAN head (12 weeks) stained for bone (alizarin red) and cartilage (alcian blue). http://php.med.unsw.edu.au/embryology/index.php?title=File:Fetal_head_lateral.jpg