Table 1

Lack of relationship between cGMP and axon damage in response to NO

Addition	Axonopathy Index	n	cGMP	n
			pmol/mg of protein
None	22 ± 4	6	5 ± 0.4	4
PAPA/NO	216 ± 13^1-150	8	13 ± 1	4
PAPA/NO ⁺ ODQ	193 ± 10^1-150 ⁿ ^s	4	4 ± 0.2	4
PAPA/NO ⁺ IBMX	193 ± 13^1-150 ⁿ ^s	4	178 ± 4	5
8-Br-cGMP	25 ± 3^1-151	3	ND
PAPA/NO ⁺ 8-Br-cGMP	187 ± 11^1-150 ⁿ ^s	4	ND
PAPA/NO ⁺ YC-1	16 ± 2^1-151	6	321 ± 18	5
PAPA/NO ⁺ YC-1 ⁺ ODQ	18 ± 1^1-151	4	70 ± 2	4
PAPA/NO ⁺IBMX ⁺ YC-1	13 ± 2^1-151	4	831 ± 16	5

Control nerves were incubated for 6 h. The axonopathy index represents the number of axons with Feret diameter above 2.5 μm/10⁴ μm². Exposure times to PAPA/NO were 2 h (plus 2-h recovery) for assessing the axonopathy and 30 min for the cGMP response. The concentrations of compounds used were 1 mM PAPA/NO, 1 mM IBMX, 10 μM ODQ, 30 μM YC-1, and 1 mM 8-Br-cGMP. Values are means ± S.E.M.

↵1-150 , P < 0.001 versus control;
↵1-151 , not significant versus control; ^ns, not significant versus PAPA/NO alone.