Table 2. 3kDa dextran tracer penetration in fixed control and mutant sciatic nerves at 1h.

Mean penetration (both sides) in fibers of all sizes, measured in teased preparations from WT, Caspr-null, cst-null and shaking mutants. Overall caliber of myelinated fibers measured from the Hoffman images, is approximately the same in WT, Caspr-null and cst-null mutants. Shaking fibers show a significantly reduced fiber diameter because their myelin sheaths are thinner (see text). 3kDa tracer penetration at 1h in the Caspr-null mice is comparable to normal, slightly reduced in the cst-null mice and almost double in the shaking mice. p values show significance in mutant vs WT measurements

	WT	Caspr-null	cst-null	shaking
# mice	15	2	2	12
# nodes	238	33	41	179
Mean fiber diam. μm±SD	9.1±1.9	9.5±2.0	8.8±1.6	8.2±1.8*
Mean penetration μm±SD (both sides)	11.2±5.6	11.4±3.8	9.3±3.5*	22.1±9.7***
p value		0.79n.s.	0.004	6.5×10−32

^*p<0.05;

^***p<0.001;