Table 1.

Effects of the reeler mutation on the entorhino-hippocampal pathway in vitro: pattern of entorhinal innervation

Culture condition	Number of co-cultures
Culture condition	wt	wt(−)	wt/rl	rl(−)	rl	Total
7 DIV
E^+/+/H^+/+	12	3	0	0	0	15
E^rl/+/H^rl/+	11	1	0	0	0	12
E^rl/rl/H^rl/rl	0	0	0	6	13	19
E^rl/rl/H^rl/+	30	11	0	0	0	41
E^rl/+/H^rl/rl	0	0	0	13	17	30
15 DIV
E^+/+/H^+/+	12	0	0	0	0	12
E^rl/+/H^rl/+	13	0	0	0	0	13
E^rl/rl/H^rl/rl	0	0	0	3	18	21
E^rl/rl/H^rl/+	14	1	0	0	0	15
E^rl/+/H^rl/rl	0	0	0	3	11	14

Entorhino-hippocampal co-cultures were prepared from +/+,rl/+, and rl/rl tissue, and the entorhino-hippocampal pathway was traced with biocytin and fixed after 7 and 15 DIV. Co-cultures were classified according to the pattern of entorhinal innervation in the SLM/ML. wt, Wild-type pattern: entorhinal fibers target to the stratum lacunosum-moleculare and molecular layer occupying the entire thickness of these layers, with a high density of innervation (>10 fibers/75 μm), and single fibers exhibit abundant collateral branches and axonal varicosities. wt−, Scarce wild-type pattern: similar to the pattern described in wt, but with a decreased density of innervation (<10 fibers/75 μm). rl,reeler-like pattern: the entorhinal termination in the stratum lacunosum-moleculare is very scarce and restricted to the vicinity of the hippocampal fissure, with fibers following straight courses and exhibiting very few axonal collaterals and varicosities; projection to the dentate gyrus appears densely packed in the outer molecular layer (>20 fibers/75 μm), with abundance of collateral branches and axonal boutons; presence of misrouted fibers in stratum radiatum and stratum pyramidale of the CA1–CA3 regions and in the hilus. rl−, Scarce reeler-like pattern: similar to the pattern described in rl, with a decreased density of innervation (<10 fibers/75 μm) in the dentate gyrus. wt/rl, Wild-type/reeler pattern: co-cultures showing intermediate (rl) or (wt) pattern of termination.