maternal recognition of pregnancy Flashcards
conceptus definition
membranes + embryo
luteotropic signal
signal that regresses the CL
anti luteolytic signal
signal that prevents regression of the Cl
what is maternal recognition of pregnancy
conceptus signals presence to mother, leading to a change in maternal physiology
what physiological changes occur due to recognition of pregnancy
-progesterone production by ovary
-increased vascularization of local endometrium
-increased production of histotroph for conceptus
what causes the down-regulation of oxytocin hormone receptors
IFN-t
stepwise mechanism when INF-T is present
-oxytocin receptors downregulated
-PGF2a decrease and PGE2 increase
-anti luteolytic effect
stepwise mechanism when INF-T is absent
-oxytocin binds to receptors
-increased production of PGF2a
-luteolytic effect
T/F E2 is essential for fetal development
FALSE. it is not essential for
-pre implantation development
-conceptus elongation
-early CL maintenance
what what used to knockout aromatase to study the effect of E2 on early pregnancy
CYP19A1
how does the horse conceptus signal pregnancy
it rolls around in the uterus
when does the horse conceptus interdigitate to uterus to start growth
day 18 post ovulation
T/F almost all animals have an accessory CL
FALSE. its unique to horses
what causes the production of an accessory CL
eCG
eCG
-what is it produced by
-what is its function
-when is it produced
-produced by endometrial cups
-acts like FSH and LH, invades endometrium by chorionic girdle cells of embryonic vesicle
-production starts 40-60 days post fertilization
LH surge length mare vs. others
mare: prolonged
others: brief
egg transport mare vs. others
mare: unfertilized eggs retained in oviduct
others: non fertilized and fertilized eggs transported
foal heat mare vs. others
mare: estrus response 5-18 days post partum
others: N/A
what species rely on CL for progesterone production for entire pregnancy
sow and doe
what organs produce progesterone throughout ewe pregnancy
CL: first 40 days
placenta: last 100 days
what organs produce progesterone throughout cow pregnancy
CL: first 128 days
placenta: after day 128
what organs produce progesterone throughout mare pregnancy
original CL: first 35 days
accessory CL: 40-180 days
placenta:160-180
what secretes hCG
trophectoderm
what is the function of hCG
prevent CL regression
when does hCG production increase
7-10 days post-fertilization
what is INF-T produced by
trophoblast
T/F INF-T is specific to pregnancy
false
