INVESTIGADORES
RAMOS Jorge Guillermo
artículos
Título:
Collagen remodelling in the guinea-pig uterine cervix at term is associated with a decrease in PR expression
Autor/es:
RODRÍGUEZ HA; KASS L; VARAYOUD J; RAMOS JG; ORTEGA HH; MUÑOZ DE TORO M; LUQUE EH
Revista:
MOLECULAR HUMAN REPRODUCTION.
Referencias:
Año: 2003 vol. 9 p. 1 - 7
ISSN:
1360-9947
Resumen:
In human and guinea-pig parturition, progesterone withdrawal and
estrogen action are not mediated by changes in their circulating
levels. Instead, these events might be promoted by changes in the
responsiveness of the uterus and cervix to progesterone and estrogen
via changes in their receptors. In this study, the guinea-pig model was
used to investigate whether high levels of progesterone and estrogen at
term are associated with regional changes in PR and ERalpha levels in
uterus and cervix. PR and ERalpha profiles were established in both
subepithelium and the muscular layer of the cervix and the lower
uterine horns during pregnancy, parturition and postpartum; while
collagen remodelling was measured in the subepithelium. Our data showed
that collagen remodelling involved in cervical ripening is temporally
and spatially associated with a decrease in PR, whereas high expression
of ERalpha is observed. This association was found in the subepithelium
of the cervical tissue but not in the same region of the uterus. The
muscular region of the cervix and uterus also present a transiently
decreased expression of PR while ERalpha levels remain high. Thus, the
present results indicate that, before parturition, diminished
responsiveness of the cervix to progesterone might be caused by a
decrease in PR levels and that this may be the mechanism of functional
progesterone withdrawal. The guinea-pig was further validated as an
animal model for human parturition studies.