PMID- 12388473
OWN - NLM
STAT- MEDLINE
DCOM- 20030114
LR  - 20200930
IS  - 0363-6119 (Print)
IS  - 0363-6119 (Linking)
VI  - 284
IP  - 1
DP  - 2003 Jan
TI  - ERK1/2-mediated phosphorylation of myometrial caldesmon during pregnancy and 
      labor.
PG  - R192-9
AB  - We used a timed-pregnant rat model to track changes in myometrial contractility 
      during pregnancy and labor and to correlate these changes with upstream signaling 
      events. Myometrium was harvested from CO(2)-euthanized rats. Although contraction 
      amplitudes increased at 16 and 20 days of pregnancy, contraction incidence and 
      area under the force curve were inhibited, consistent with the myometrial 
      quiescence of pregnancy. The Ca(2+) sensitivity of contraction was decreased at 
      20 days of pregnancy and this was partially reversed in labor. The protein 
      content of h-caldesmon (h-CaD) was increased in pregnancy. A 40-fold increase in 
      the signal from a phospho-CaD antibody specific for phosphorylation at an ERK1/2 
      site occurred during labor. ERK1/2 activation increased significantly at the 
      onset of labor. Myosin light chain phosphorylation (LC20-P) increased 
      significantly in labor compared with the nonpregnant state. Thus we conclude that 
      the increase in CaD protein content during pregnancy may contribute to a 
      suppression of the contractility of pregnant myometrium. Conversely, CaD 
      phosphorylation, through an ERK1/2-mediated signaling pathway, as well as an 
      increase in basal LC20-P, is suggested to contribute to the reversal of 
      inhibition and promote contraction of the uterus during labor.
FAU - Li, Yunping
AU  - Li Y
AD  - Department of Anesthesia and Critical Care, Beth Israel Deaconess Medical Center, 
      Harvard Medical School, Boston, MA 02215, USA. yli1@caregroup.harvard.edu
FAU - Je, Hyun-Dong
AU  - Je HD
FAU - Malek, Sabah
AU  - Malek S
FAU - Morgan, Kathleen G
AU  - Morgan KG
LA  - eng
GR  - GM-07592/GM/NIGMS NIH HHS/United States
GR  - HL-31704/HL/NHLBI NIH HHS/United States
GR  - HL-42293/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
DEP - 20021003
PL  - United States
TA  - Am J Physiol Regul Integr Comp Physiol
JT  - American journal of physiology. Regulatory, integrative and comparative 
      physiology
JID - 100901230
RN  - 0 (Antibodies)
RN  - 0 (Calmodulin-Binding Proteins)
RN  - 0 (Myosin Light Chains)
RN  - EC 2.7.11.24 (Mitogen-Activated Protein Kinase 1)
RN  - EC 2.7.11.24 (Mitogen-Activated Protein Kinase 3)
RN  - EC 2.7.11.24 (Mitogen-Activated Protein Kinases)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Animals
MH  - Antibodies
MH  - Calcium/metabolism/pharmacology
MH  - Calmodulin-Binding Proteins/chemistry/*metabolism
MH  - Enzyme Activation
MH  - Female
MH  - Immunoblotting
MH  - Labor, Obstetric/*metabolism
MH  - Mitogen-Activated Protein Kinase 1/*metabolism
MH  - Mitogen-Activated Protein Kinase 3
MH  - Mitogen-Activated Protein Kinases/*metabolism
MH  - Molecular Weight
MH  - Myometrium/drug effects/enzymology/*metabolism
MH  - Myosin Light Chains/chemistry/metabolism
MH  - Phosphorylation
MH  - Pregnancy
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Uterine Contraction/metabolism
EDAT- 2002/10/22 04:00
MHDA- 2003/01/15 04:00
CRDT- 2002/10/22 04:00
PHST- 2002/10/22 04:00 [pubmed]
PHST- 2003/01/15 04:00 [medline]
PHST- 2002/10/22 04:00 [entrez]
AID - 00290.2002 [pii]
AID - 10.1152/ajpregu.00290.2002 [doi]
PST - ppublish
SO  - Am J Physiol Regul Integr Comp Physiol. 2003 Jan;284(1):R192-9. doi: 
      10.1152/ajpregu.00290.2002. Epub 2002 Oct 3.