ANSC 431 Exam 3

placenta after 60 days

progesterone production location in humans

placenta

progesterone production location in rodents

CL until day 50

progesterone production in sheep

cow progesterone production

produced by CL (ovary) throughout pregnancy, but placenta produces enough on day 215

sow progesterone production

from the ovary

mare progesterone production

from the ovary until ~day 180 when the placenta takes over

hCG

stimulates P4 secretion and prevents luteolysis

eCG

FSH-like, stimulates ovulation of follicles and production of accessory CL

eCG production location

endometrial cups of mares

placental lactogen

shift metabolism to provide energy for fetus and stimulate development of mammary gland

relaxin

increase uterine quiescene and blood vessel compliance, also assists with cervical dialation at parturition

relaxin production location

ovary and/or placenta depending on the species

progesterone functions

causes differentiation of embryo to prepare it for implantation, immunosuppressive to prevent rejectuion of the fetus, maintains uterine quiescence and an unriped cervix while regulating the mammary gland

estrogen functions during gestation

increase uterine blood flow, uterine growth by stimulating proliferation of smooth muscle cells. Also increases steroid binding protein synthesis by the liver and stimulates growth of breat ductal system

progesterone and estrogen levels throughout pregnancy

both increase during pregnancy, particularly during the second half

how are estrogens made

fetus produces DHEA in the adrenal which travels to the placenta. DHEA is converted ot various estrogens, these travel to teh maternal side to increase maternal blood estrogen levels.

how is progesterone made

from pronenlone in the palcenta which is stimlated by LDL cholesterol on the maternal side

morning sickness factor

grwoth differentiation factor 15 (GDF15)

why GDF15 problematic during pregnancy

placenta produces it also which can lead to higher levels than normal

GDF15 binding

receptors are on the hindbrain which controsl food intake, nausea and loss of body weight, therefore GDF15 binding increased causes the increases of these symptoms and therefore causes morning sickness

treatments for morning sickness

exposure to small amounts of GDF15 before pregnancy, and ot use a compound to reduce GDF15 levels during pregnancy

hcG species

humans

PSPB species

cattle

relaxin pregnancy test species

cats and dogs

getational diabetes

the development of insulin resistance during pregnancy. Due to change in energy needs of the fetus during the second half of pregnancy as the mother switches from an anabolic to catabolic state.

gestational diabetes risk factors

advanced maternal age, obestity, increasing cortisol levels, increased placental lactogen, catabolic state in 2nd half of pregnancy

glucose tolerance test

used to diagnose gestational diabetes

how glucose tolerance test works

women are given a glucose drink and then blood samples are collected and checked for glucose levels at several points after the drink is consumed. If two samples are above given values then it is likely that the women will develop gestational diabetes.

fetal ACTH

the first hormone that shows measurable changes in preparation for parturition

parturition activation pathway

fetal stress increases fetal ACTH, then fetal cortisol increases with increases enzyme levels and PGF2alpha. Placental P4 and enzymes stimulates E2 which increases secretions by the female tract and therefore increases lubrication. PGF2a causes luteolysis and stimulates relaxin which caues pelvic ligament stretching. PGF2alpha also works with E2 to increases myometrial contractions, then pressure, cervical stimulate and oxytocin. This leads to maximum pressure and parturition.

increase during parturition

prostaglanding and estrogen

decrease during parturition

progesterone (this is receptor number in humans)

how do we know parturition is initiated by the fetus

destruction of the pituitary gland in lambs resulted in poorly developed adrenal galnds and a longer pregnancy. Destroying adrenal cortex, but not medulla extended getation. Exogenous ACTH, cortisol and dexomethesone could induce premature labor.

connexins

connect cells and improve internal communication (CAPs)

prostaglandin receptor

stimulates smooth muscle contractions when bound to by prostaglandin (CAP)

oxytocin receptor

prep for labor by controlling contractions (CAPs)

Braxton-hicks contractions

false contractions felt by women during pregnancy, are irregular and can start as early as 6 weeks, but not felt until 2nd or 3rd trimester. Uncomfortable but not painful.

role of relaxin on uterus during pregnancy

works with progesterone to keep uterus quiescent during most of pregnancy

effects of relaxin on the cervix

at the time of parturition it softens and ripens the cervix for labor to facilitate a rapid and safe delivery

what hormon does relaxin work with on the cervix

estrogen

cervix ripening

a softening and widening of the cervix in preparation for expulsion of the fetus

effects of cervical ripening on cervix

the cervix increaes in size which is primarily due to increased water intake by the tissues

prostaglandin and oxytocin role during parturition

stimulate smooth muscle contractions that stem from the uterus

methods to induce labor

sweeping of the membranes, foley catheter, amniotomy, treating with prostaglandin, exogenous oxytocin (pitocin), (need to use a physical method in combination with oxytocin)

reasons to induce labor

maternal illness, fetal health, long pregnancy, premature rupture of membranes, infections

cesarian delivery reasons

placenta low in uterus and covers cervix (placenal previa), separation of placenta from uterus, previous cearian, baby too large, in breech or transverse position, failure to progress in labor

IVF stimulate protocol

fertility injections, start cycle monitoring, measure hormone levels and preform ultrasounds, hCG to induce ovulation, egg retrivel procedure, freeze cultured embryos

GnRH agonist/antagonist purpose in IVF

shut off the pituitary gland to prevent it from producing GnRH

FSH purpose in IVF.

stimulate follicle development

hCG purpose in IVF

induce ovulation

progesterone purpose in IVF.

required for implantation and a successful pregnancy

important parameters for egg harvest in IVF

follicle size and blood estradiol levels

morphological factors decreasing embryo quality grade

prescence and amount of fragmentation, ICM that has very few cells and very little or no compaction

age of the women

main factor that effects the number of eggs harvested, pregnancy rates, and birth rate in IVF patients

ICSI

the injection of sperm into the egg by the use of a needle generally used when sperm abnormalities are present

principal behind sequential and global medium for blastocyst transfer

there is evidence that there is a switch in carbohydrate metabolism near the 4-8 cell stage of development.

early embryo energy source

pyruvate/lactate

blastocyst energy source

glucose

changes to freezing procedure

higher concentration of cryoprotectant is needed in comparison to sperm and freezing time needs to be much faster

vitrification

oocyte freezing procedure name

FSH

main hormone needed for oocyte maturation in vitro

improvements to in vitro culture systems

development of sequential media, transfering the embryo at blastocyst stage, using a single culture medium

ovarin hyperstimulation syndrome

exaggerated painful response to injected hormone medication used to stimulate the ovaries

cause of ovarian hyperstimulation syndrome

too many follicles grow and luteinize, release angiogeni and inflammatory factors and excess fluid. Risk factors are pcos, younger age, high antral follicle count, known sensitivity to fertility drugs

preimplantation genetic diagnosis

a biopsy procedure to detect genetic diseaes that may be at a higher frequency in IVF children

DNA for cloning

comes from the nucleus of the somatic cell

where does DNA for cloning go

into the oocyte

cloning procedure

one donor provides an oocyte and the other provides a somatic cell. The DNA is removed from the oocyte as is the nucleus form the somatic cell. This nucleus is then injected into the oocyte to provide the DNA. After chromosome condnesation, several nuclear transfer embryos are placed into the oviduct of the foster mother who births the cloned animals.

pig cloning success

90%

horse cloning success

13-20%

cattle cloning success

low

why cloning success rate low

mainly due to compromised placental development and point in the cell cycle where cloning takes place

nuclear reprogramming

the epigenetic reinstruction of the nucleus to undertake an alternative genetic program, usually a program in embryogenesis

methylation

the DNA is chemically altered by adding methyl groups to particular sites within the sequence of the gene which represses gene activity

histolation

alteration in the histone proteins around which the chromosomal DNA is wrapped

epigenetic asymmetry and cloning success

can cause placental abnormalities and decrease the success of cloning

methods to improve cloning success rates

syncing the donor cells in G0 with roscovitine, using HDAC inhibitors which incresases acetylation of histones

large offspring syndrome

very large fetuses that can’t be delivered natrually. fetal membranes are heavier, there are fewer placentomes.

affects of LOS on fetus and placenta

increase in cardiovascular disease, peri-natal death is common. Placentation is very shallow and componsatory growth occurs in a more dramatic fashion

reason for LOS

problem with epigenetic factors

hydrops

presence of acute accumulation of fluid in the allantois, enlarged placentomes, oversized fetus → overall a serious animal welfare issue

therapeutic cloning

nuclear transplantation to produce stem cells. derivation of stem cells from the product of nuclear transfer.

reproductive cloning

a procedure that generates individuals with identical nuclear genomes

where to primordial germ cells come from

migrate from the yolk sac to the primitive kidney

sex determination

genotypic sex → decides an organisms sex chromosomes

sex differentiation

phenotypic sex (physical and hormonal process that builds female or male body structures)

Kleinfelters syndrome (XXY)

example of sex development disorder due to nondisjunction of chromosomes (sterile with testicular hypoplasia)

anti-mullarian hormone

blocks development of the female tract

testosterone/5a-dihydrotestosterone

promotes wolffian duct formation

Sry

the master gene for mammalian sex determination, its prescence is sufficient to induce male development

male

wollfian/mesonephric duct

female

Mullerian/paramesonephric duct

female tract

vagina, endometrium, cevix, ovary, oviduct/fallopian tube, uterus

male reproductive organs

epididymis, vas deferens, seminal vesicle, prostate, bulbourethral galnd, testicle, penis

hermaprodite

congenital malformation in sexual development, true have combination of ovaries and testes or ovatestes

psuedohermaphrodite

male (has testes but female external genitalia) or female (have ovaries but male external genetalia). They don’t have both ovaries and testes

sex-linked traits

traits that come from genes on the sex-chromosomes (X/Y) such as colorblindness

sexual differentiation disorder examples

congenital adrenal hyperplasia, 5a reductase deficiency, androgen insensitivity syndrome

tortoiseshell coat color development

one x-chromosome is inactivated to form a barr body. One of these chromosomes has the orange allelle and the other a black allele. The active chromosome is random, so a pattern of orange and black coat color is formed.

seminiferous tubules

where spermatogenesis takes place