Gu and Reproduction PDF

Gu and Reproduction Reproductive Embryology -Anatomic differentiation occurs in utero -FINAL MATURATION OF REPRODUCTIVE ORGANS DOES NOT OCCUR UNTIL PUBERTY -Chromosomal sex is determined at fertilization Sexual differentiation -Before sexual differentiation, two parallel duct systems are develop...

Gu and Reproduction Reproductive Embryology -Anatomic differentiation occurs in utero -FINAL MATURATION OF REPRODUCTIVE ORGANS DOES NOT OCCUR UNTIL PUBERTY -Chromosomal sex is determined at fertilization Sexual differentiation -Before sexual differentiation, two parallel duct systems are developed near the gonads -Men= Mesonephric Wolffian duct -Women= Paramesonephric Mullerian duct -Differentiation depends on if there is testosterone present= leading factor of male or female Reproductive Embryology MALES -Primordial cells—Spermatogonia + Sertoli cells— MALE GAMETES -Leydig cells secrete Testosterone -Wolffian ducts will later become the two epididymitis, vas deferens, and seminal vesicles in a male Reproductive Embryology FEMALES -Primordial–OOGONIA—granulosa and thecal cells—-estrogen and progestin -No testonere present so the Wolffian duct degenerates and Mullerian ducts are what are kept. -Mullerian ducts become the fallopian tubes, uterus, and upper portion of vagina -Once cells mature, give rise to secrete estrogen and progestin in puberty. Differences in Sexual development -Gential tubercle become penis or clitoris -Complete Androgen Insensitivity syndrome (CAIS) -Genotypically male, phenotypically female -Lack androgen receptors so testosterone can’t do it’s job appropriately -Often diagnosed with failure of onset of menstrual cycle -Lack a uterus and have undescended testicles where ovaries would have been Deficiency of 5 alpha-reductase -Phenotypically male, phenotypically female -Testosterone cannot convert so decreased dihydrotestosterone (DHT) -Masculinization at puberty (deep voice, facial hair, muscle bulk) Congenital Adrenal Hyperplasia -Genotypically female, phenotypically male -Impaired cortisol synthesis -Excessive/ deficient production of androgens/hormones -Virilization of female uterus -Male outside parts yet, female genetically Puberty Males -9-14 years old (testes begin to enlarge) -Scrotum and penis enlarge -Increased testosterone= More and thicker hair, deeper voice and increased skeletal muscle strength Females -8-10 years old (breast enlargement begins) -Ovarian cycle begins -Enlargement of uterus, labia majora and labia minora -Widening of the pelvis, deposition of fat on hips and thighs LH and FSH surge. Puberty terms Menarche= first period Adrenarche= right before puberty—-surge of hormones and androgens that lead to pubic and axillary hair Precocious puberty= Early puberty—starting puberty before 8 in females and 9 in boys Gynecomastia= enlargement of the male breast, occurs when estrogen levels are elevated in neonatal period or during male puberty -Also occurs in elderly men as well Male Anatomy: Testicles– secreting testosterone and making sperm Epididymis— where the sperm are stored Vas deferens– expels the sperm to the urethra during ejaculation Seminal vesicles— Produce fluid that has nourishment for ejaculated sperms Prostate gland— Secretes acid phosphate, contracts to deliver secretions into the urethra, possibly liquifies semen until the female reproductive tract. -Makes the prostate specific antigen (psa is the main area to look at for prostate cancer) 3 phases of spermatogenesis: 1. Proliferation of spermatogonia -To produce a large populations of cells -Spermatogonia+mitosis= primary spermatocyte (!st) 2. Generation of genetic division via meiosis -After first meiotic division–secondary spermatocyte -2nd meiotic division—spermatid 3. Maturation of sperm -Specialization that allows the journey to the oocyte -Spermatid + cellular remodeling= (spermatogenesis) spermatozoa Mitotic division= primary (meiosis) Meiotic division= secondary Meiosis a second time to become spermatid Hormonal control of Spermatogenesis -LH and FSH secreted by anterior pituitary -Controlled by hypothalamus -Lh goes on to stimulate Leydig cells for testosterone -FsH: -Stimulates Sertoli cells- secrete androgen binding protein to increases testosterone Spermatogenesis (Testicle) -Inside the testicle= Tightly coiled seminiferous tubules -Seminiferous tubules= where sertoli cells are. -Germinal cells undergo mitosis= primary spermatocyte Primary spermatocyte goes through meiosis I === secondary Secondary goes through II= spermatid TAKES ABOUT 74 Days to produce full grown sperm In this process for 60 days In epididymis for 14 days to mature To make 74 days. Phases of Ejaculation 1. Erection (NITRIC OXIDE) -Sinusoidal spaces fill with blood 2. Emission -Spermatozoa and seminal plasma move into the urethra 3. Ejaculation -Semen ejected from urethra Stages of Sexual Response 1. Excitement -Penile erection, vaginal lubrication 2. Plateau Vascular congestion (blood form)-- encouragement of scrotum and labia 3. Orgasm -Ejaculation (males), pleasure, rhythmic contractions of perineum  4. Resolution -Penile flaccidity, vaginal relaxation, refractory period (males) Female anatomy Ovaries: -where oogenesis occurs so where eggs are formed (major source of sex steroids and hormones) Fallopian tubes: -Transport ovum and sperm to the fertilization site Uterus: -support growing fetus -Undergo dramatic changes during the menstrual cycle Vagina Fallopian tubes -Transport ovum and sperm to fertilization site -Fimbra, Ampulla, Isthmus, Intramural section -AMPULLA IS WHERE MOST FERTILIZATION OCCURS Fimbria= Fingerlike projections that help receive ovum released by ovary NOT CONNECTED TO OVARY Ampulla= Dilated part where MOST FERTILIZATION OCCURS Isthmus= Thinner area that holds zygo te for 2-3 days after fertilization Intramural section= Where the fallopian tube meets the uterus Pelvic Inflammatory Disease -Caused by ascending Sexual transmitted disease (chlamydia and gonorrhea) -Fallopian tubes can become scarred and increases ectopic tubal pregnancy -MOST COMMON SITE OF ECTOPIC PREG NANCY IS AMPULLA Uterus -Pear shaped muscular organ -Growth during pregnancy occurs because of hyperplasia -3 parts: 1. Fundus= area above opening of fallopian tubes 2. Corpus= main body of the uterus 3. Cervix= lower portion of the uterus that extends and protrudes into the vagina Vagina -Tube extending from cervix to vaginal opening -Mucus-secreting glands to allow lubrication of intercourse VULVA -Collective name for female external genitalia 1. Lower 1/3 of vagina 2. Labia 3. CLIT Oogenesis In utero 1-2 million to be sent to ovum when puberty occurs Undergo mitosis= primary oocytes until puberty Primary goes when puberty occurs then meiosis I= Secondary oocytes Meiosis II until fertilization= Become ovum post fertilization Cycle is completed at the time of fertilization ALL OCCURS IN FOLLICLES IN OVARY GRAAFIAN FOLLICLE MERGEZES AS DOMINANT Menstrual cycle -Controlled by hypothalamic- pituitary ovarian axis -Sequence of events that occurs EVERY 28 DAYS -1. Follicular phase= day 1 -2. Ovulatory phase= day 13-15 -3. Luteal phase= 15-28 days Follicular Phase -Day 1-14 -Day 1= 1st day bleeding -Primary follicles develop and dominant follicle emerges Ovulatory phase -13-15 days -Lh surge, increased estrogen secretion -Primary oocyte= completed meiosis I Dominant follicle ruptures—--ovulation Oocyte is released Luteal Phase -Day 15-28 -Corpus Luteum is formed -No pregnancy– corpus luteum degenerates -Pregnant—- Continued progesterone secretion is essential Fertilization 100-600 million sperms are deposited into vagina Sperms swimming motion+ uterus contracting + cilia propelling oocyte== fertilization -8 stages of fertilization Fertilization problems -Hydatidiform mole (benign molar) -Can be complete or incomplete -Means molar pregnancies are incompatible with life -Cluster of grapes appearance Implantation -In AMPULLA OF FALLOPIAN TUBES -Fertilized egg develops 6-7 days prior to implantation “blastocyst” -3 stages of implantation 1. Apposition= -Formation of loose connection in endometrium 2. Adhesion= -Where microvilli actually extend from the cell 3. Invasion= -Where the embryo becomes completely embedded in the endometrium of the uterus Placenta ORGAN CARRYING CHILD -Functions: -Transports materials between maternal and fetal circulations -Secretion of hormones required to maintain pregnancy HCG= 1st trimester Progesterone = 2nd trimester Estrogen= 3rd trimester -Placenta also transports: -glucose, ldl, amino acids, large molecules -All located in the uterus in the amniotic sac, amniotic fluid (which is the baby’s urine) 9 WEEKS= PROGESTERONE 12 WEEKS= ESTROGEN Estrogen= Stimulates growth of uterine muscle and development of mammary glands Progesterone= maintaining the endometrium and reducing uterine contractions Both drop off significantly at the end of the pregnancy near the time of birth. -Progesterone dropping helps to let uterine contractions -Estrogen levels dropping helps with milk let down Placental peptides Two types: -Human chorionic gonadotropin (HCG) -Human chorionic somatomammotropin hormone (HCS) HCG FUNCTIONS -Keeps corpus luteum from degenerating -Allows continued progesterone to be secreted for the early pregnancy until the placenta can take over. HCS -Stimulates fatty acid and ketone production -Promotes mammary gland development -Creates a state of insulin resistance in the mother to promote availability of glucose to fetus Maternal Adaptation of pregnancy - BLOOD VOLUME TO 40 to 50 % -Alveolar ventilation increases -Blood coagulability increases -Suppression of cellular immunity -Glomerular filtration rate increases 40-50% -Nutritional demands (iron and protein) Parturition -Initiation of labor is poorly understood -Once labor is initiated= needed to keep going 1. Prostaglandins 2. Oxytocin Stages: 0-3 total of 4. 0. Majority of pregnancy with uterus inactive/ relaxed 1. Cervix starts to dilate and amniotic fluid ruptures 2. Fetus is expelled from uterus 3. Placenta is birthed Lactation -Breast tissue growth and differentiation during pregnancy -15-20 lobes per breast. 20-40 terminal ducts per lobe. -Majority of breast milk is Triglycerides (3-5 %) -Colostrum= Liquid Gold (first few days after birthing) Endocrine control of lactation Prolactin (by anterior pituitary) -essential for milk production Oxytocin -Posterior pituitary -Stimulates milk expression from breast -Let down can be conditioned. Positive feedback loop. Milk production Occurs 2 DAYS AFTER PARTURITION Suckling= Both prolactin and oxytocin infant suckling. Positive feedback loop.