HBS 2.2 Endocrine system

Endocrine gland

organ that makes hormones and releases them into the blood stream

feedback loops

process where change in systems can trigger a certin result

Postive feedback loops

creates an amplification affect (ex: child birth)

Negative feedback

makes a change internally to maintain homeostasis (ex:sweating to release heat)

Why are feedback loops important to homeostasis?

enables the system to respond to varying external factors

Hypothalamus

links endocrine to CNS

pituitary gland

receives signals from hypothalamus, makes hormones or secretes hormones from the hypothalamus

pineal gland

produces and secreates melatonin

thyroid gland

controls growth, energy use, and body temperature

thymus gland

produces and matures immune cells (T lymphocytes)

pancreas

produces glucagon and insulin

adrenal glands

hormones in response to stress and blood pressure

ovarys

makes estrogen and progesteronet

testicles

makes sperm and testostrone

Hormone step 1

travels in blood until they reach target cellH

Hormone step 2

target cells have receptors, hormones fit into it

Hormone step 3

Receptors are specific, hormone binds and activates cell signaling process

steriod

hormones, diffuse through the membrane, binds/activates DNA

peptid

hormone, binds to receptor on target cell, activates cell signaling process

insulin

can bind to receptors on the same cell, diffusable, uses paracrine signaling

Estrogen

uses long distance endocrine signaling

Insulin function

lowers blood glucose by absorbing sugar from the blood stream

glucagon

raises blood glucose by signaling liver to release stored sugar

T4

regulates metabolism, energy, and growth

TSH ( thyroid-stimulating hormone)

signals thyroid gland to produce T3/T4

TRH (Thyrotropin-releasing hormone)

released from hypothalamus to trigger pituitary gland to make TSH

GH ( growth hormone)

stimulates body growth

LH ( luteinizing hormone)

triggers ovulation and testosterone production

FSH ( follicle-stimulating hormone)

helps develop ovarian follicle and produces sperm

Estrogen function

regulates female reproductive development

testosterone

controls male reproductive development

progesterone

prepare and maintains uterus for birth and regulates cycle

How to diagnose diabetes

fasting blood glucose, AIC testf

fasting blood glucose

fasting, checks glucose over 8 hours, diabetes (126 mg)/ pre-diabetes ( more than 100 mg)

AIC test

measure blood sugar for 3 months, diabetes (6.5+) pre-diabetes (5.7-6.5)

pre-diabetes

cells dont respond to insulin, resolve with diet/excerise

diabetes 1

immune system attack itself, destroys beta cells, solved by insulin injections and blood glucose monitoring

diabetes 2

insulin resistance, cant make enough insulin, solved by lifestyle changes, insulin medication

GDM

Hormones made by placenta in pregnancy, insulin resistance, solved by diet, blood glucose monitoring

EDCs

Endocrine disrupting chemicals, chemicals in the environment that alter the function of hormones

EDCs examples

food and cosmetics

How EDCs affect sex hormones?

affects sex hormones function by interfering with sex hormones balance and pathway

How do EDCs affect on development?

mimick/block sex hormones, reproductive tract malformations during developments

Grave’s Disease

(Hyperthyroidism)

High levels of thyroid hormones. Metabolism accelerated causing heart beat (irregular) increase and weight loss

Hyperplasia-->Myasthenia Gravis

Enlarged Thymus, affecting immune system  cell overproduction→ Ach receptors affected→ muscle weakness/fatigue

Hypopituitarism (Growth Hormone Deficiency)

Pituitary gland does not release sufficient GH→ development affected (bones/tissues). Affects metabolism

Hypoparathyroidism (Hypocalcemia)

Low PTH hormone, low calcium and vitamin D. Muscle contraction issues.

Pituitary Tumor

Low TSH= less thyroid hormones

Hypothyroidism→ weight gain

Low LH→ low sperm count

Increased GH→ Acromegaly (abnormal growth bones and muscle)

Addison’s disease

Adrenal glands don’t produce sufficient ACTH→ low cortisol and aldosterone.  Stress sxs (blood pressure and glucose) and sodium/potassium levels.