TY - JOUR
T1 - Estrogen-dependent facilitation on spinal reflex potentiation involves the Cdk5/ERK1/2/NR2B cascade in anesthetized rats
AU - Peng, Hsien Yu
AU - Chen, Gin Den
AU - Tung, Kwong Chung
AU - Chien, Ya Wen
AU - Lai, Cheng Yuan
AU - Hsieh, Ming Chun
AU - Chiu, Chun Hsien
AU - Lai, Cheng Hung
AU - Lee, Shin Da
AU - Lin, Tzer Bin
PY - 2009/8
Y1 - 2009/8
N2 - Cyclin-dependent kinase-5 (Cdk5), a proline-directed serine/threonine kinase, may alter pain-related neuronal plasticity by regulating extracellular signal-related kinase-1/2 (ERK1/2) activation. This study investigated whether Cdk5-dependent ERK activation underlies the estrogen-elicited facilitation on the repetitive stimulation-induced spinal reflex potentiaton (SRP) that is presumed to be involved in postinflammatory/neuropathic hyperalgesia and allodynia. Reflex activity of the external urethra sphincter electromyogram evoked by pelvic afferent nerve test stimulation (TS; 1 stimulation/30 s for 10 min) and repetitive stimulation (RS; 1 stimulation/1 s for 10 min) was recorded in anesthetized rats. TS evoked a baseline reflex activity, whereas RS produced SRP. Intrathecal (it) β-estradiol facilitated the repetitive stimulation-induced SRP that was reversed by pretreatment with the estrogen receptor anatogonist ICI 182,780 (10 nM, 10 μl it), Cdk5 inhibitor roscovitine (100 nM, 10 μl it), ERK inhibitor (U-0126; 100 μM, 10 μl it) and N-methyl-D-aspartate (NMDA) NR2B subunit antagonist (Co-101244; 100 nM, 10 μl it). Moreover, ERα (propylpyrazoletriol; 100 nM, 10 μl it) and ERβ (diarylpropionitrile; 100 μM, 10 μl it) agonists both facilitated the SRP, similar to results with a β-estradiol injection. In association with the facilitated RS-induced SRP, an intrathecal β-estradiol injection elicited ERK1/2 and NR2B subunit phosphorylation that were both reversed by intrathecal roscovitine and U-0126. These results indicated that the Cdk/ERK cascade, which is activated by ERα and ERβ, may subsequently phosphorylate the NR2B subunit to develop NMDA-dependent postinflammatory hyperalgesia and allodynia to maintain the protective mechanisms of the body.
AB - Cyclin-dependent kinase-5 (Cdk5), a proline-directed serine/threonine kinase, may alter pain-related neuronal plasticity by regulating extracellular signal-related kinase-1/2 (ERK1/2) activation. This study investigated whether Cdk5-dependent ERK activation underlies the estrogen-elicited facilitation on the repetitive stimulation-induced spinal reflex potentiaton (SRP) that is presumed to be involved in postinflammatory/neuropathic hyperalgesia and allodynia. Reflex activity of the external urethra sphincter electromyogram evoked by pelvic afferent nerve test stimulation (TS; 1 stimulation/30 s for 10 min) and repetitive stimulation (RS; 1 stimulation/1 s for 10 min) was recorded in anesthetized rats. TS evoked a baseline reflex activity, whereas RS produced SRP. Intrathecal (it) β-estradiol facilitated the repetitive stimulation-induced SRP that was reversed by pretreatment with the estrogen receptor anatogonist ICI 182,780 (10 nM, 10 μl it), Cdk5 inhibitor roscovitine (100 nM, 10 μl it), ERK inhibitor (U-0126; 100 μM, 10 μl it) and N-methyl-D-aspartate (NMDA) NR2B subunit antagonist (Co-101244; 100 nM, 10 μl it). Moreover, ERα (propylpyrazoletriol; 100 nM, 10 μl it) and ERβ (diarylpropionitrile; 100 μM, 10 μl it) agonists both facilitated the SRP, similar to results with a β-estradiol injection. In association with the facilitated RS-induced SRP, an intrathecal β-estradiol injection elicited ERK1/2 and NR2B subunit phosphorylation that were both reversed by intrathecal roscovitine and U-0126. These results indicated that the Cdk/ERK cascade, which is activated by ERα and ERβ, may subsequently phosphorylate the NR2B subunit to develop NMDA-dependent postinflammatory hyperalgesia and allodynia to maintain the protective mechanisms of the body.
KW - Cyclin-dependent kinase-5
KW - Estradiol
KW - Extracellular signal-related kinase
KW - Hyperalgesia
KW - NR2B
KW - Pelvic pain
KW - Spinal reflex potentiaton
UR - http://www.scopus.com/inward/record.url?scp=68049085523&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=68049085523&partnerID=8YFLogxK
U2 - 10.1152/ajpendo.00129.2009
DO - 10.1152/ajpendo.00129.2009
M3 - Article
C2 - 19531642
AN - SCOPUS:68049085523
SN - 0193-1849
VL - 297
SP - E416-E426
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 2
ER -