Table 1.

Frequency of endothelial fenestrations (f), junctional complexes (j.c.) and pinocytotic vesicles (p.v.) in intraneural and perineural capillaries during murine embryonic development.

Day of embryonic development	Intraneural capillaries			Perineural capillaries
	f	j.c.	p.v.	f	j.c.	p.v.
E9		No capillaries present		0.9	3.2	2.0
E10	nd	1.7	2.9	0.13	2.9	1.9
E12	nd	2.58	2.33	nd	3.25	3.0
E14	nd	2.29	1.57	nd	2.43	3.29
E17	nd	2.25	1.63	nd	2.75	4.13

Values were determined as follows: number of f, j.c., or p.v. divided by the number of capillaries examined (7–17 capillaries; mean values are shown). n.d., not detected (Bauer et al., 1993).