CaMKII was activated by NMDARs, PP2B
(calcineurin) was activated by VGCCs, and phosphodiesterases (PDEs) were activated by either NMDARs (to mimic spines in cortical slices) or [IP.sub.3] receptors (to mimic spines in hippocampal cultures).
PP2B activity was measured using a commercial kit with slight modification, as described previously (Ogasawara et al.
Although pisiferic acid activated PP2C by up to 1.3-fold under the same conditions, it inhibited PP2B activity with a 50% inhibitory concentration ([IC.sub.50]) of 118.3 [micro]M (Fig.
Protein phosphatases (PP1 and PP2B
) were able to dephosphorylate the PKC[alpha] phosphorylated N-DAT; however, none of the tested protein phosphatases dephosphorylated the ERK1 phosphorylated N-DAT.
Estas incluyen fodrina y [alfa]-actinina-2 como elementos estructurales, tambien la molecula reguladora calmodulina, proteinfosfatasa serina/treonina (PP2B
), proteina neuronal sensora de calcio VILIP, calretinina y caldendrin, una proteina recientemente identificada.
PP1 and PP2A, known as protein serine/threonine phosphatases (PPs), are a family of metalloproteins comprising seven subtypes PP1, PP2A, PP2B
, PP4, PP5, PP6 and PP7.
Calcineurin (CN)  forms part of the serine/threonine phosphatase (PPase) family (EC 3.13.16), which contains 4 known members, PP1, PP2A, PP2B
(CN), and PP2C (1).
For instance, it has been proposed that tonic NMDA receptor stimulation plays a crucial role in limiting MAP2 phosphorylation in hippocampal slices through a mechanism involving stimulation of the calcium/calmodulin-dependent phosphatase, to be PP2B
or calcineurin [11, 13].
To summarize, the main core of kinases and phosphatases includes CaMKII, PKA, protein phosphatase 1 (PP1), and protein phosphatase 2b (PP2b
, calcineurin) (Fig.
Koekkoek et al., "Purkinje cell-specific knockout of the protein phosphatase PP2B
impairs potentiation and cerebellar motor learning, " Neuron, vol.
Both drugs have the same target: the serine/threonine phosphatase calcineurin (CN), or PP2B
. One important substrate of this phosphatase is the nuclear factor of activated T cells.
Phosphatase Inhibitor PP1 Okadaic acid PP2A Okadaic acid PP2B
(calcineurin) CsA PP2C - Table 2.