TY - JOUR
T1 - Activation of cAMP-dependent protein kinase A in prefrontal cortex impairs working memory performance.
AU - Taylor, J. R.
AU - Birnbaum, S.
AU - Ubriani, R.
AU - Arnsten, A. F.
PY - 1999
Y1 - 1999
N2 - Activation of the adenylyl cyclase-cAMP-protein kinase A (PKA) intracellular signaling cascade is necessary for long-term memory consolidation in brain regions such as the hippocampus. However, the role of the PKA cascade in the working memory functions of the prefrontal cortex (PFC) is unknown. The present study examined the effects of manipulating PKA activity in the PFC using the cAMP stereoisomers Sp-cAMPS and Rp-cAMPS, which activate and inhibit PKA, respectively. Animals received bilateral infusions of Sp-cAMPS and/or Rp-cAMPS into the PFC immediately before testing on the delayed alternation task, a test of spatial working memory that depends on the integrity of the PFC. Low doses of Sp-cAMPS (0.21, 2. 1, or 21 nmol/0.5 microl) produced a marked, dose-dependent impairment in working memory performance. The impairment produced by infusion of Sp-cAMPS (21 nmol/0.5 microl) was fully reversed by co-infusion of Rp-cAMPS (21 nmol/0.5 microl), consistent with actions on PKA. Rp-cAMPS (21 or 42 nmol/0.5 microl) by itself had no effect on performance. These results indicate that activation of the PKA intracellular signaling cascade in the PFC impairs working memory performance. The current findings contrast with studies of long-term memory consolidation, in which inhibition of PKA with agents such as Rp-cAMPS impaired memory consolidation (Bernabeu et al., 1997; Bourtchouladze et al., 1998), whereas enhancement of the PKA pathway improved memory (Bernabeu et al., 1997; Barad et al., 1998). These results demonstrate that discrete cognitive processes subserved by different cortical regions are mediated by distinct intracellular mechanisms.
AB - Activation of the adenylyl cyclase-cAMP-protein kinase A (PKA) intracellular signaling cascade is necessary for long-term memory consolidation in brain regions such as the hippocampus. However, the role of the PKA cascade in the working memory functions of the prefrontal cortex (PFC) is unknown. The present study examined the effects of manipulating PKA activity in the PFC using the cAMP stereoisomers Sp-cAMPS and Rp-cAMPS, which activate and inhibit PKA, respectively. Animals received bilateral infusions of Sp-cAMPS and/or Rp-cAMPS into the PFC immediately before testing on the delayed alternation task, a test of spatial working memory that depends on the integrity of the PFC. Low doses of Sp-cAMPS (0.21, 2. 1, or 21 nmol/0.5 microl) produced a marked, dose-dependent impairment in working memory performance. The impairment produced by infusion of Sp-cAMPS (21 nmol/0.5 microl) was fully reversed by co-infusion of Rp-cAMPS (21 nmol/0.5 microl), consistent with actions on PKA. Rp-cAMPS (21 or 42 nmol/0.5 microl) by itself had no effect on performance. These results indicate that activation of the PKA intracellular signaling cascade in the PFC impairs working memory performance. The current findings contrast with studies of long-term memory consolidation, in which inhibition of PKA with agents such as Rp-cAMPS impaired memory consolidation (Bernabeu et al., 1997; Bourtchouladze et al., 1998), whereas enhancement of the PKA pathway improved memory (Bernabeu et al., 1997; Barad et al., 1998). These results demonstrate that discrete cognitive processes subserved by different cortical regions are mediated by distinct intracellular mechanisms.
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U2 - 10.1523/jneurosci.19-18-j0001.1999
DO - 10.1523/jneurosci.19-18-j0001.1999
M3 - Article
C2 - 10479716
AN - SCOPUS:0242689354
SN - 0270-6474
VL - 19
SP - RC23
JO - The Journal of neuroscience : the official journal of the Society for Neuroscience
JF - The Journal of neuroscience : the official journal of the Society for Neuroscience
IS - 18
ER -