Table 2.

Comparison Lucifer Yellow Protocols to Study GJIC in Early Xenopus Embryos

Study	Measured Lucifer transfer at stages		How passage via cytoplasmic bridges was excluded	All data werecollected from	Control for reflectionand scattered light
	No. of cells
Warner et al. 1984	32		No fluorescent dextran injections Lucifer yellow was injected into one group of embryos and fluorescent dextran was injected into a separate group of embryos	Whole-mounts	Few sibling embryos were analyzed on frozen or plastic sections
Guthrie 1984	32	Whole-mounts
Guthrie et al. 1988 Olson et al. 1991	16–128 32	Whole-mounts Whole-mounts
				Nagajski et al. 1989		32	No fluorescent dextran injections	Whole-mounts	No sections
Olson and Moon 1992	32	}	Lucifer yellow was injected into one group of embryos and fluorescent dextran was injected into a separate group of embryos	Whole-mounts	No sections
Guger and Gumbiner 1995	32			Whole-mounts	No sections
Krufka et al. 1998	32			Whole-mounts	No sections
Levin and Mercola 1998	8–16		Fluorescent dextran was injected in a mixture solution with Lucifer yellow	Whole-mounts	No sections
This study	16–128		Fluorescent dextran was injected in a mixture solution with Lucifer yellow	Paraffin or frozen sections	All embryos were analyzed on either 12- μm paraffin or 14-μm frozen sections.