Table 1.

Summary of the effects of inhibitors on 30-min and 24-h retention.

Inhibitor	L-NAME	ODQ	L-DIL	W-7	KN-62	DDA	KT5720	CHX
Target	NOS	sCG	CNG channel	CaM	CaMKII	AC	PKA	Protein synthesis
Effects on 30-min retention after multiple-trial conditioning	No effect	No effect	No effect	No effect	No effect	No effect	No effect	No effect
Effects on 24-h retention after multiple-trial conditioning	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired
Effects on 24-h retention after single-trial conditioning
+NO-donor	No effect	Fully impaired	–	–	–	–	Fully impaired	Fully impaired
+cGMP analog	No effect	No effect	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired	Fully impaired
+Ca2+ ionophore	–	No effect	No effect	Fully impaired	Fully impaired	Fully impaired	–	–
+AC activator	–	No effect	No effect	No effect	Fully impaired	Fully impaired	–	–
+cAMP analog	No effect	No effect	No effect	No effect	No effect	No effect	Fully impaired	Fully impaired

NOS, NO synthase; sGC, soluble guanylyl cyclase; CNG channel, cyclic nucleotide-gated channel; CaM, calmodulin; AC, adenylyl cyclase; PKA, protein kinase A; L-DIL, L-cis-diltiazem; DDA, 2′5′-dideoxyadenosine; CHX, cycloheximide. Data for L-NAME, L-DIL, and W-7 experiments are from Matsumoto et al. (2006); Data for ODQ, DDA and KT5720 experiments are from Matsumoto et al. (2006, 2009); Data for KN-62 experiments are from Mizunami et al. (2014); Data for CHX experiments are from Matsumoto et al. (2003, 2006). The concentrations of the administrated drugs were as follows: L-NAME (400 μM), ODQ (200 μM), L-DIL (1 mM), W-7 (200 μM), KN-62 (2 mM), DDA (1 mM), KT 5720 (200 μM), CHX (10 mM), NO-donor SNAP (200 μM), cGMP analog 8-br-cGMP (200 μM), Ca²⁺ ionophore A23178 (200 μM), AC activator forskolin (200 μM), cAMP analog 8-br-cAMP (200 μM), and DB-cAMP (200 μM).