Fig. 4.

Zebrafish axial motoneurons are immunoreactive to CR and PV. a Representative images of the double-labeled motoneurons with CR and PV. b Quantification of the percentage of the motoneurons that express both CR and PV. c Whole mount images showing the expression of CR and PV in distinct motoneuron pools (slow, intermediate and fast). Single channel views of the respective images shown for better visualization of CR or PV positive cells. Arrowheads indicate the double-labeled cells. d Color coded quantification of the CR and PV expression in distinct populations of neurons. The vast majority of motoneurons contain PV. CR expression is localized mainly in the motoneurons of the fast module