TY - JOUR
T1 - Time-dependent involvement of cAMP and cGMP in consolidation of object memory: Studies using selective phosphodiesterase type 2, 4 and 5 inhibitors
AU - Rutten, K.
AU - Prickaerts, J.H.H.J.
AU - Hendrix, M.
AU - van der Staay, F.J.
AU - Sik, A.
AU - Blokland, A.
PY - 2007/1/1
Y1 - 2007/1/1
N2 - The present study investigated the time-dependent memory enhancing properties of three selective phosphodiesterase inhibitors (PDE-I) vardenafil (PDE5-I), rolipram (PDE4-I) and BAY 60-7550 (PDE2-I) in the object recognition task. In particular, the time-dependent involvement of cAMP and cGMP in memory consolidation was assessed by altering the time points of drug administration. Vardenafil (1 mg/kg, p.o.), rolipram (0.03 mg/kg, i.p.), and BAY 60-7550 (3 mg/kg, p.o.) were tested in rats with a 24 h delay between the learning and the test trial. The PDE-Is were administered at different time points, i.e. directly after, I h, 3 h and 6 h after the first trial. Using a 24 It interval, vardenafil only showed an effect on object memory when injected directly after trial 1, roliprarn only showed an improvement when injected 3 h after trial I and BAY 60-7550 improved memory when injected either directly after or 3 h after trial 1. No treatment effects were found when the compounds were administered 1 h or 6 h after the first trial. Our results extend our previous data that different types of PDE-Is affect different stages of memory consolidation. Moreover, the present study provides further support that selective PDE-Is can influence memory consolidation in a time-dependent manner, assumingly by elevating central cAMP and cGMP levels.
AB - The present study investigated the time-dependent memory enhancing properties of three selective phosphodiesterase inhibitors (PDE-I) vardenafil (PDE5-I), rolipram (PDE4-I) and BAY 60-7550 (PDE2-I) in the object recognition task. In particular, the time-dependent involvement of cAMP and cGMP in memory consolidation was assessed by altering the time points of drug administration. Vardenafil (1 mg/kg, p.o.), rolipram (0.03 mg/kg, i.p.), and BAY 60-7550 (3 mg/kg, p.o.) were tested in rats with a 24 h delay between the learning and the test trial. The PDE-Is were administered at different time points, i.e. directly after, I h, 3 h and 6 h after the first trial. Using a 24 It interval, vardenafil only showed an effect on object memory when injected directly after trial 1, roliprarn only showed an improvement when injected 3 h after trial I and BAY 60-7550 improved memory when injected either directly after or 3 h after trial 1. No treatment effects were found when the compounds were administered 1 h or 6 h after the first trial. Our results extend our previous data that different types of PDE-Is affect different stages of memory consolidation. Moreover, the present study provides further support that selective PDE-Is can influence memory consolidation in a time-dependent manner, assumingly by elevating central cAMP and cGMP levels.
U2 - 10.1016/j.ejphar.2006.11.041
DO - 10.1016/j.ejphar.2006.11.041
M3 - Article
SN - 0014-2999
VL - 558
SP - 107
EP - 112
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
IS - 1-3
ER -