Tunica albuginea: connective tissue cortex of the ovary (and testis)

Cumulus oophorus: granulosa cells on which the ovum is projected into the follicular antrum

Corona radiata: granulosa cells that surround the ovum

Atresia: follicular degeneration; fate of most ovarian follicles

Zona pellucida: glycoprotein coat of the ovum

Ovulation stigma: protrusion along the ovarian wall indicative of impending rupture

Fossa: ovarian depression from which ovulation occurs in some species (eg., mare)

Bursa: a blind sac continuous with the oviduct that surrounds the ovary in some species (eg., rodents); prevents ectopic pregnancy

Common epithelial ovarian cancer: > 90% of all ovarian cancers arise from ovarian surface epithelium that is traumatized (DNA damage) at ovulation; very lethal because it usually goes undiagnosed until advanced metastasis

Mesovarium: supportive ligament of the ovary

Mesosalpinx: supportive ligament of the oviduct

Mesometrium: supportive ligament of the uterus

Diapedesis: passage of cells through the essentially intact wall of blood vessels; stimulated by estradiol in the uterus of the proestrous bitch and metestrous cow

Spiral artery: deep endometrial blood vessels of some primates (humans, apes, Old World monkeys); the tips become exposed and bleed during tissue degeneration/sloughing associated with menses

Dysmenorrhea: uterine cramping associated with menses

Endometriosis: ectopic growth of uterine tissue - usually displaced to the oviducts and pelvic cavity during menstruation; can cause adhesions, pain, and infertility

PMS: premenstrual syndrome; associated with the luteal phase; symptoms include moodiness, weight gain, breast tenderness; etiology uncertain

Premature ovarian failure: autoimmune follicular exhaustion (menopause) at an early age (< 40 years)

Polar body: nuclear fragment of oogenesis (meiotic maturation)

Luteinization: transformation of follicular (theca, granulosa) cells into luteal (small, large) cells

Angiogenesis: neovascularization; characteristic of luteinization

Luteinized unruptured follicle syndrome: luteinization without ovulation; a subtle cause of infertility; produced experimentally by NSAIDs


Folliculogenesis: primordial > primary (fully grown oocyte with a single layer of granulosa cells) > secondary (granulosa proliferation into multiple layers) > tertiary (antral formation, thecal differentiation) > preovulatory (Graafian) corpus hemorrhagicum (ruptured follicle, luteinization) > corpus luteum > corpus albicans (regressed CL)


Theca externa: outer connective tissue/smooth muscular layer of the follicle; contractile activity contributes to the ovulatory process

Theca interna: loose connective tissue matrix between the theca externa and membrana granulosa; contains capillary beds and steroidogenic cells

Granulosa: steroidogenic epithelial cells that line the follicular cavity; interact with the ovum


Oviduct: infundibulum (expanded funnel-end; ovum pick-up); ampulla (body; fertilization); isthmus (utero-tubal junction; controls sperm and ovum transit)

Uterus: endometrium (mucosa/submucosa; implantation/gestation)

Stratum functionalis: luminal component of the endometrium that is sloughed after steroid withdrawal

Stratum basalis: (intact) basal component of the endometrium that proliferates to rebuild the functionalis

Myometrium: muscularis of the uterus (sperm transport, parturition)

Cervix: neck of the uterus; sphincter that controls uterine access (sperm entry, parturition) or not (pregnancy)

Vagina: copulatory organ


Didelphic: no uterine body, two uterine horns, two cervices, two vagina (marsupials, platypus)

Duplex: no body, two horns, two cervices, one vagina (rodents, rabbit)

Bicornuate: small body, two horns, one cervix, one vagina (pig, marine mammals)

Bipartite: large body, two horns, one cervix, one vagina (ruminants, horse, cat, dog)

Simplex: dominant body, no horns, one cervix, one vagina (primates)


Reflex ovulation: occurs in response to neural (mating) stimulation of the POA (rabbit, cat)


Steroid feedback: low progesterone/low estradiol (early follicular phase) > ARC activated; low progesterone/high estradiol (late follicular phase) > increased pituitary sensitivity to GnRH/POA activated (positive feedback); high progesterone (luteal phase) > negative feedback


Hormonal interrelationships of spontaneous (estrous) cycles: increased PGF2a > decreased luteal progesterone > increased tonic GnRH production > increased FSH/LH > increased follicular estradiol production > increased pituitary GnRH receptors/surge GnRH release > preovulatory gonadotropin surge > ovulation/luteinization > decreased (granulosa) inhibin > secondary FSH surge > follicular growth (ovulation at next estrus) increased progesterone (negative feedback)


Two-cell/two-gonadotropin mechanism of follicular steroidogenesis: LH > theca interna cell > androgen; FSH > granulosa cell > estradiol


Proestrus: luteolysis > preovulatory follicular growth

Estrus: sexual receptivity; ovulation; oviduct/uterine contractility; endometrial proliferation; cervical dilation/mucus secretion; vaginal cornification

Metestrus: CL formation

Diestrus: CL function; uterine quiescence; secretory endometrium; cervical constriction/plug formation

[proestrus + estrus = follicular phase; metestrus + diestrus = luteal phase]


Durations (days) of estrus and estrous cycles: rat/mouse (0.5, 4); sheep (2, 17); pig (2, 21); cattle (0.5, 21); horse (5, 21); dog (7, 60)


Advantages of estrous synchronization: efficient use of AI; uniform calf crop

Disadvantages of estrous synchronization: cost; labor; skill; facilities; lower conception than natural breeding

Progestin: mimic the luteal phase - follicular growth, estrus, and ovulation follow removal of feedback inhibition; advantages - good synchronization (timed breeding is an option) and anestrous animals can respond; disadvantages - expense and labor intensive

Prostaglandin: causes luteal regression (removal of negative feedback); advantage - economical (one-injection system); disadvantages - animals must be cycling and in the responsive luteal phase, more variable return to estrus than progestin (estrous detection recommended); can cause abortion


Menstrual cycle: menses (d 1-5); follicular phase (d 6-13); ovulatory phase (d 14); luteal phase (d 15-28)

Comparison to estrous cycle: menstruation; sexual receptivity outside the ovulatory phase; luteal estradiol production; long follicular phase (no secondary FSH surge)


Contraceptive mechanisms of oral steroids: ovulation blockade; alterations of cervical mucus (plug), endometrial development, and tubal motility

Noncontraceptive medical benefits: decreased incidences of ovarian and endometrial neoplasia, dysmenorrhea, PMS, pelvic inflammatory disease, cystic ovarian disease, endometriosis, benign breast disease, break-through bleeding, iron deficiency anemia, androgen-dependent acne


Menopausal etiology: estrogen depletion due to chronic atretic oocyte/follicular loss

Symptoms: emotional upset; hot flashes; osteoporosis (estrogens aid in bone calcification); hypersecretion of gonadotropins (hMG) - removal of ovarian steroid negative feedback


Follicular rescue/superovulation: FSH, PMSG, hMG


Role of prostaglandins in ovulation: granulosa dispersion and oocyte maturation (PGE2); collagenolysis, ischemia, contractility (PGF2a)

Role of PGF2a in luteolysis: vasoconstriction; decreased membrane fluidity; stress response/apoptosis; immune/inflammatory reaction


Oogenesis: mitosis oogonia (fetal) > meiotic (prophase) I arrest (dictyate) > growth (cytoplasm accumulation) - primary oocyte > preovulatory gonadotropin surge > resumption of meiosis I > unequal cytokinesis (first polar body extrusion) - secondary oocyte > start of meiosis II > ovulation > meiotic arrest (metaphase II) > sperm penetration > completion of meiosis II (second polar body) > ootid


Role of the uterus in luteal regression: hysterectomy in farm animals causes a prolongation of luteal function (ie., the uterus is the source of PGF2a - which reaches the ovaries either by local veno-arterial transfer [ruminants] or the systemic circulation [horse]; hysterectomy does not alter ovarian cyclicity in primates (ie., the source of luteolysin is the ovaries)

PUZZLE: grid, clues, solution.