TABLE 1.

Effects of the NOS inhibitor l-NAME and the NO donor detanonoate on behavior in anxiolytic tests

Values shown are means ± S.E. l-NAME (50 mg/kg) did not affect behavior in any of the tests in mice exposed to restraint stress (data not shown). Detanonoate (DETA; 0.5 mg/kg) did not affect behavior in the elevated plus-maze or hole-board in nonstressed mice; however, it did reduce entry latency and increase ambulation and rearing in nonstressed mice (p < 0.05; data not shown). Detanonoate + Bay 60-7550 (BAY; 1 mg/kg) increased percentage of open-arm time in the elevated plus-maze and reduced entry latency and increased ambulation in the open-field in nonstressed mice (p < 0.05; data not shown) but did not affect the other measures. Detanonoate + ND7001 increased percentage of open-arm time in the elevated plus-maze in nonstressed mice (p < 0.05; data not shown) but did not affect the other measures. The effect of Bay 60-7550 and ND7001 alone or in the presence of stress is shown in Figs. 4 to 6.

Anxiolytic Test Behavioral Measure	Vehicle No Stress	l-NAME No Stress	Vehicle Stress	DETA Stress	DETA + BAY Stress	DETA + ND7001 Stress
Elevated plus-maze
% Open-arm entries	32.0 ± 3.4	13.6 ± 2.3*	4.6 ± 2.3**	32.5 ± 4.8†	39.6 ± 2.8††	40.1 ± 2.6††
% Open-arm time	10.8 ± 3.4	1.2 ± 1.3*	0.8 ± 0.5*	6.0 ± 5.4	20.2 ± 2.6††	29.0 ± 1.9††
Hole-board
Head-dips	17.7 ± 1.4	8.6 ± 1.8*	5.2 ± 1.3*	14.7 ± 1.2†	15.5 ± 1.0††	22.9 ± 3.2††
Head-dip time (s)	29.6 ± 2.8	11.6 ± 1.7*	6.4 ± 1.1**	26.2 ± 2.9††	33.6 ± 4.7††	28.1 ± 4.0††
Open-field
Entry latency (s)	12.3 ± 2.2	28.6 ± 3.2	20.0 ± 3.0	4.6 ± 1.1†	7.8 ± 4.3	6.6 ± 2.3†
Ambulation (crosses)	153.5 ± 9.6	84.2 ± 6.4*	108.3 ± 3.9*	184.3 ± 19.5††	190.5 ± 13.9††	161.8 ± 12.1†
Rears	50.5 ± 1.9	19.7 ± 3.1	26.2 ± 4.7*	58.6 ± 3.4††	62.0 ± 2.0††	55.1 ± 3.5†

^* Significantly different from vehicle + no stress, p < 0.05;

^** p < 0.01.

^† Significantly different from vehicle + restraint stress, p < 0.05;

^†† p < 0.01.