Endocrinology Week 2

What gland is shaped like a pinecone?

Pineal gland

What is the AKA of the pineal gland?

epithalamus

What is the primary secretion of the pineal gland?

Melatonin

What controls circadian rhythms?

Melatonin

What does melatonin secretion inhibit, thus delaying onset of puberty?

GNRH (gonadotropin releasing hormone)

What does GNRH control the release of?

FSH and LH

What is the term fro calcification of the pineal gland?

Brain sand

When does brain sand usually occur?

20-30 yo

What occurs when GNRH starts to pulse?

Puberty

Why do elders have a hard time getting to sleep?

Melatonin levels decline with age

T or F: Melatonin is an antitumor factor

True

What is a benign tumor of the pineal gland consisting of functional cells?

Pinealoma

Where are the satiety centres found?

Hypothalamus

Which regulatory centres are found in the hypothalamus?

Osmoreceptors

Thermostat

Glucostat and lipostat (energy balance)

Autonomic centers for BP and HR

Autonomic centers for respiratory rate

Which hormones released in the blood stream are created hypothalamus?

ADH and oxytocin

What is the AKA of the posterior pituitary?

Neurohypophysis

What is the AKA of the anterior pituitary?

Adenohypophysis

What is the name of a circulatory system that starts and ends with capillaries?

Portal system

What are the 2 portal systems of the human body?

Hepatic portal system

Hypophyseal portal system

What does the hypophyseal portal system connect?

The hypothalamus to the anterior pituitary

What controls all secretions of the anterior pituitary?

The hypothalamus

What controls the release of Gonadotropins from the anterior pituitary?

GNRH (Gonadotropin Releasing Hormone)

What does ADH stand for?

Antidiuretic hormone

What is the AKA of ADH?

Arginine Vasopressin

What are the two functions of ADH?

Increases permeability of the collecting duct to water

Causes vasoconstriction

How does ADH increase water resorption from the collecting duct?

Installs aquaporins

What influences the production of ADH?

Osmoreceptors in the hypothalamus

What are the 2 functions of oxytocin?

Quick birth

Milke let-down reflex

What is the name of the oxytocin derivative used to induce labor?

Pitocin

What muscles does oxytocin act on during labor?

Uterine myometrium

What muscles does oxytocin act on during milk let-down?

Myoepithelial cells of lactiferous glands

What is oxytocin used for primarily in males?

Balances stress responses

What is a secondary effect of oxytocin during birthing?

Prevents excess bleeding

What do statin drugs do?

Prevents the production of cholesterol

What tonically inhibits prolactin?

Dopamine

Where is most dopamine produced?

In the substantia nigra

What type of growth does prolactin promote?

Lymphocyte cloning

Why did we call the pituitary the master gland?

Because pituitary hormones are found in the blood while releasing hormones are not

Where does the adenohypophysis develop from?

Rathke's pouch

What is the AKA of growth hormone?

Somatotropin

T or F: Growth hormone is only active in anabolic states

False (it is active for protein-sparing energy consumption in the catabolic state)

What does GH cause the Liver to produce in the anabolic state?

Somatomedins

What is the AKA of somatomedins?

Insulin-like growth factors

What hormone causes increased cartilage formation, skeletal growth, protein synthesis, and cell proliferation extraskeletally?

Somatomedin

Which hormone has anti-insulin actions in the catabolic state?

Somatotropin

What processes are promoted by GH in the catabolic state?

Lipolysis and glycogenolysis

T or F: Somatotropin reduces blood sugar

False (it increases blood sugar by blocking insulin)

What hormone inhibits growth hormone?

Somatostatin

Why are growth hormone injections dangerous?

They have a diabetogenic effect

Which hormone causes liberation of lipids from female fat?

Prolactin

Which fats are stored in females for brain growth?

DHA and EPA

What is the main function of prolactin in males?

Promotes cloning of lymphocytes

Which hormones are generated by the effect of ACTH?

Cortisol

Aldosterone

Sex steroids

What is the effect of cortisol?

gluconeogenesis and anti-inflammation

What is the effect of aldosterone?

save sodium and secrete potassium

What sex steroid is primarily released from the adrenal cortex?

Testosterone

What do adrenal sex steroids enable?

Gondal development

T or F: Increased levels of TSH increase body temperature

True

What stimulates the anterior pituitary to secrete TSH?

TSHRH from the hypothalamus

T or F: FSH and LH have different structures in men compared to women?

False (they are the same in men and women)

What does FSH promote in men?

Gametogenesis

What does LH promote in men?

Testosterone production

What do both FSH and LH act on in women?

The follicle surrounding the egg

What is the neutral term for sex gland?

Gonad

What are the 2 functions of gonads?

Manufacture sex cells (gametes)

manufacture / secretion of sex hormones

What cells does FSH act on in men?

sustentacular cells of the seminiferous tubule

What is the effect of FSH on the sustentacular cells?

Makes them receptive to testosterone

What cells does LH act on in men?

interstitial cells of Leydig

What is the name of the sustentacular cells that support spermatogenesis?

Setoli

What do the interstitial cells of leydig produce?

androgens

What does the follicle surrounding the ovum produce?

Female hormones (estrogen)

How many follicles does FSH act on?

12

A spike in what hormone causes ovulation?

LH

What does the left-over follicle secrete?

Progesterone

What hormone is secreted pre-ovulation?

Estrogen

What hormone is secreted post-ovulation?

Progesterone