NM704 Exam: Questions With Solutions (100%
Accurate)
Phase 0 → Quiescence Right Ans - Hormones that inhibit
labor/contractions:
Progesterone
Prostacyclin
Relaxin
Nitric oxide & others
Phase 1 → Activation Right Ans - Uterotropins are Estrogen &
Prostaglandins
-stimulate up regulation of myometrial receptors for oxytocin &
prostaglandins & gap junctions
Phase 2 → Stimulation Right Ans - Uterotonins- oxytocin & protiglandins
-promote labor progression
, Phase 3 → Involution Right Ans - Uterine involution after birth
-mediated by oxytocin & possibly thrombin
Progesterone Right Ans - Uterotropin. Effects the uterus. Dominant in
Quiescence and inhibits regular uterine contractions.
Estrogen Right Ans - Uterotropin. Effects the uterus. Dominant in
Activation phase.
Prostaglandins Right Ans - Uterotonin. Effects the contractions. Dominant
in activation and stimulation phase. They facilitate contractions and increase
myometrial sensitivity to oxytocin and stimulate gap junctions.
Oxytocin Right Ans - Uterotonin. Effects the contractions, maintains labor
but does not initiate it. Dominant in Stimulation Phase. Amount of oxytocin
increases and peaks during second stage of labor and enhanced by fetal
oxytocin synthesis. Released in a pulsatile fashion.
Oxytocin receptors Right Ans - The number of receptors and their
sensitivity influences the strength and frequency of contractions. The affinity
of oxytocin for the receptors increases. The number of receptors present on
the myometrium peaks in early labor. Labor and mechanical stretch increase
expression of oxytocin receptors.
Gap junctions Right Ans - proteins that create a line of communication
between two adjacent myocytes. The action potentials act through gap
junctions and cause a
Myometrium Right Ans - it is the bulk of the uterus. It is located between
the decidua and perimetrium and has four muscle layers and promote and
inhibit contractions. The muscle is thickest at the fundus and has the greatest
contraction strength. The muscle is thinner towards the isthmus. This is the
muscle that is made of smooth muscle fibers and connective tissue (elastin
and collagen). The myocytes have contractile ability. Prostaglandins stimulate
myocytes to depolarize creating a wave of contraction with action potentials
being sent from gap junction to gap junction like a domino effect. Intermittent
contractions allow for reperfusion.
Accurate)
Phase 0 → Quiescence Right Ans - Hormones that inhibit
labor/contractions:
Progesterone
Prostacyclin
Relaxin
Nitric oxide & others
Phase 1 → Activation Right Ans - Uterotropins are Estrogen &
Prostaglandins
-stimulate up regulation of myometrial receptors for oxytocin &
prostaglandins & gap junctions
Phase 2 → Stimulation Right Ans - Uterotonins- oxytocin & protiglandins
-promote labor progression
, Phase 3 → Involution Right Ans - Uterine involution after birth
-mediated by oxytocin & possibly thrombin
Progesterone Right Ans - Uterotropin. Effects the uterus. Dominant in
Quiescence and inhibits regular uterine contractions.
Estrogen Right Ans - Uterotropin. Effects the uterus. Dominant in
Activation phase.
Prostaglandins Right Ans - Uterotonin. Effects the contractions. Dominant
in activation and stimulation phase. They facilitate contractions and increase
myometrial sensitivity to oxytocin and stimulate gap junctions.
Oxytocin Right Ans - Uterotonin. Effects the contractions, maintains labor
but does not initiate it. Dominant in Stimulation Phase. Amount of oxytocin
increases and peaks during second stage of labor and enhanced by fetal
oxytocin synthesis. Released in a pulsatile fashion.
Oxytocin receptors Right Ans - The number of receptors and their
sensitivity influences the strength and frequency of contractions. The affinity
of oxytocin for the receptors increases. The number of receptors present on
the myometrium peaks in early labor. Labor and mechanical stretch increase
expression of oxytocin receptors.
Gap junctions Right Ans - proteins that create a line of communication
between two adjacent myocytes. The action potentials act through gap
junctions and cause a
Myometrium Right Ans - it is the bulk of the uterus. It is located between
the decidua and perimetrium and has four muscle layers and promote and
inhibit contractions. The muscle is thickest at the fundus and has the greatest
contraction strength. The muscle is thinner towards the isthmus. This is the
muscle that is made of smooth muscle fibers and connective tissue (elastin
and collagen). The myocytes have contractile ability. Prostaglandins stimulate
myocytes to depolarize creating a wave of contraction with action potentials
being sent from gap junction to gap junction like a domino effect. Intermittent
contractions allow for reperfusion.
