Gonads Physio - PBT3

Where is gonadal hormone production initiated? (We begin w/ GnRH)

Arcuate nucleus of Hypothalamus

Testosterone is produced in the Testes via what?

LH → LH-R in the Leydig cell

What promotes Spermatogenesis (production of sperm?)

Testosterone-ABP complex in the Sertoli cell

What makes ABP (androgen-binding protein)?

FSH → FSH-R in the Sertoli cell

What makes Androgen in the Ovaries?

LH → LH-R in the Thecal cell

What INC levels of Aromatase?

FSH → FSH-R in the Granulosa cell

How is Estradiol synthesized?

Androgen (from the Thecal cell carried in) + Aromatase (this takes place in the Granulosa cell)

The inner lining of the uterus; if fertilization occurs, the egg is implanted here

Endometrium

What houses the Granulosa cells AND the Egg?

Follicle

What happens to the follicle upon fertilization?

Burst → Release egg

That which is ruptured then becomes a Corpus Luteum

Its role is to produce and release Progesterone

Corpus Luteum

-Follicular

-Luteal

Phases of the Menstrual Cycle

What is required to cause the RUPTURING of the follicle, thereby releasing the egg (ovum) into the fallopian tube?

Surge in LH and FSH

This is the first half of the cycle (first ~14 days), PRIOR TO Ovulation

-Estradiol is important here and is primarily involved in the development of the egg and follicle in the ovaries (we get a surge nearing the end of this phase)

-We get a surge in LH and FSH nearing the end of this phase

Follicular Phase

This is the second half of the menstrual cycle occurring directly AFTER Ovulation

-Estradiol and Progesterone released during this phase (but more Progesterone)

Luteal Phase

-Thickens the endometrium lining

-Matures the ovarian follicles

Estradiol’s Role (why it surges Nearing Ovulation)

Requirement of the Endometrium Lining for a Fertilized Egg to attach itself to it

Must be Thick AND Soft

This serves to SOFTEN the Endometrium Lining

Progesterone

Surge in Progesterone, followed by a DROP in Progesterone (has to hit 0)

Requirement for Menses

What happens if there is NO attached fertilized egg to the Endometrium?

Endometrial lining SHEDS itself → Menses

What happens if there IS a fertilized egg attached to the Endometrium?

Progesterone levels RISE (continues to do so)

What does Estradiol inhibit during Luteal phase (this is its Neg feedback loop)

LH and FSH release from Pituitary gland

What does Progesterone inhibit during Luteal phase (this is its Neg feedback loop)

GnRH release from Hypothalamus (the arcuate nucleus portion)

-Bone growth (inhibition of Osteoclasts)

-INC body metabolism and fat deposition

-Skin changes

-Na+ and water retention

Estrogen effect in Females

Where does Sperm go through after exiting the Testes?

Vas Deferens

Seminal Vesicles

Mixes Seminal fluids (makes up 70% of semen) with Sperm

30% of semen consists of this solution produced by the Prostate

Calcium Citrate ion, Phosphate ion, Clotting enzyme, Profibrinolysin

Involved in the development of male sexual organs and brain

Testosterone in Gestation

What happens if there is NO exposure to testosterone in the 2nd trimester of gestation?

Fetus becomes a girl ❤ 👧

Development of male characteristics; we get an INC in levels

Testosterone in Puberty

Gradual decline in levels

Testosterone in Adulthood (mid-late 20s onwards)

-Body hair distribution and baldness

-Vocal changes, Acne

-INC in Protein formation, Bone matrix, Basal metabolic rate (BMR), RBCs

Testosterone Effects in Males

Irregular menstrual cycles leading to NO menses for more than 3 cycles :(

Amenorrhea

IF we get Amenorrhea BUT we have intact female reproductive anatomy, there is an issue with what?

Hypothalamic-Pituitary-Gonadal (HPG) Axis

-(Functional) Hypothalamic

-Pituitary

-Ovarian

Types of Amenorrhea

-Due to DEC’d GnRH drive → Low levels of FSH and LH

-Maybe due to abnormal activation of HPA axis (excessive production of CRH, DEC GnRH, INC cortisol levels)

-**** Excessive CRH + cortisol, Low levels of FSH and LH

-Reversible with Nutritional consultation & stress coping

(Functional) Hypothalamic Amenorrhea

A ppt is hella stressed out and has Amenorrhea. She wants to ovulate regularly again. How does she treat this?

Treat the irregular Cortisol levels first

-Due to Elevated PRL (prolactin) levels (may have Pituitary tumors)

-Other causes can be: Oral contraceptives, TCAs, Antipsychotics (e.g. Haloperidol)

Pituitary Amenorrhea (aka Hyperprolactinemia)

Prolactin secretion is controlled by what? (This inhibits Prolactin release)

Dopamine

Obstruction of Portal Vasculature by a Prolactinoma

Limits reach of DA to Prolactin secreting cells → Hyperprolactinemia

A ppt comes in and is lactating unexpectedly. She has irregular cycles and wants to ovulate properly again. How does she treat this?

D2 receptor agonists

-Bromocriptine

-Cabergoline

-D2 receptor agonists

** If drug doesn’t work, surgical removal of Prolactinoma

Treatment Option/Plan for Pituitary Amenorrhea

Due to ovarian failure (i.e. Menopause or Repeated Ovulation failure/Anovulation)

Ovarian Amenorrhea

Condition where the ovaries do NOT release an egg (ovum) during a menstrual cycle; caused by hormonal imbalances in the Hypothalamic-Pituitary function or “peripheral endocrinopathies”

Anovulation

Elevated androgen or estrogens from Peripoheral organs (mainly ovaries) → Inappropriate feedback mechs

Peripheral Endocrinopathies

-Hyperandrogenism (Cardinal feature**) and Anovulation

-50% are obese

-Hirsutism (excessive growth of dark coarse hair)

-Acne, irregular menstrual cycles

-Appearance of multiple ovarian cysts/follicles (in ultrasound)

-HIGH levels of GnRH and LH **

-Insulin insensitivity

PCOS (Polycystic Ovarian Syndrome)

Where are there a lot more follicles in a PCOS ovary?

They started the maturation process BUT due to imbalance in hormones, they did not proceed to progress the maturation- they stopped.

INC probability of:

-High blood Lipid profile

-Cardiovascular disease ❤

-Vascular Thromboembolism

-Diabetes 🍭

-***ENDOMETRIAL CANCER if untreated (no cycle in > 1 yr)

PCOS Risk Factors

-Diet and Exercise

-Monitor blood lipid

-Oral contraceptives

-Metformin (Glucophage) ** IDEAL

How to manage PCOS

Ppt comes in with PCOS. she wants to get her natural ovulation cycle again. How do we treat her?

Metformin

During Follicular feedback Loop, what STIMULATES LH and FSH

Estradiol