The Endocrine System

Hormones

For hundreds of years, humans have released countless numbers of synthetic compounds into the environment. Many pharmaceuticals, cleaning products, cancer treatments and pesticides are known endocrine disruptors and have disastrous effects on fish populations. Largemouth Bass commonly affected by endocrine disruptors Endocrine disruptors that mimic estrogen hormones have a severe impact on fish fertility and reproduction. They can lead male fish to undergo feminization, a process where males turn into females. They experience a serious decrease in testosterone level and many male fish are found with immature female eggs in their testes. Exposure to estrogen does not stop with the intersex problem. It also reduces production of immune-related proteins in fish which makes them more susceptible to disease. “Our research suggests that estrogen-mimicking compounds may make fish more susceptible to disease by blocking production of hepcidin and other immune-related proteins that help protect fish against disease-causing bacteria,” said Robertson.

What are hormones? Hormone – chemical signal made in one place and travels through body to a target organ Enable body to maintain homeostasis

Where are hormones produced? Various “glands” –Pineal gland, hypothalamus, pituitary gland, thyroid gland, parathyroid gland, thymus gland, adrenal glands, pancreatic islet cells, ovaries, uterus, and testes

Endocrine Overview GlandHormone MadeTargetEffect(s) HypothalamusVarious Main controller of the endocrine system Pituitary Gland (directly controlled by hypothalamus) Various Growth hormone, Fsh, LH, Adrenal gland and thyroid gland Various Adrenal glandsEpinephrine, norepinephrine, cortisol VariousFight-or-flight response Various cells in bodyProstaglandinsVariousFever, cramps, inflammation PancreasInsulin, glucagonCells in body, liverRegulates blood- glucose levels PinealMelatoninGonadsInhibits reproductive activites, sleep

Endocrine Overview Cont. GlandHormone MadeTargetEffect(s) ParathyroidParathyroid hormoneBone, kidneyElevates calcium levels in blood ThymusThymosinLymphocytesPlays role in immune response OvaryEstrogens, Progesterone Female reproductive structures Maturation of reproductive organs, prepares uterine lining for pregnancy TestisTestosteroneMale reproductive structures Maturation of reproductive organs Thyroid, Thyroxine, calcitoninVariousGrowth, speeds up metabolism, decreased calcium levels in blood

How Hormones Work Bind to receptors on cell surface (peptide hormones) or in cell nucleus (steroid hormones) Hormones alter what genes/enzymes are turned on and off in the target cell Steroid hormones can travel through cell membrane and nuclear membrane Peptide hormones cannot travel through cell membrane –Use second messengers to transfer signal

The ‘Master Gland” and its Master

Endocrine Disorders Goiters – too little thyroxine in blood stream Diabetes – too little insulin produced or insulin receptors not functioning properly on cells

Goiter

Endocrine Disorders Cont. Dwarfism – growth hormone from pituitary gland inhibited Gigantism – growth hormone from pituitary gland hyperactive

Acromegaly Too much growth hormone during adulthood

To much growth hormone

Tallest meets shortest man

1 foot 9.5 inches meets 8 feet 11.1 inches

Killed wife w/ cord, son strangle hold (7yrs old) & self -hung(40 yrs old) Was given to much testosterone for his hormone disorder 10 time the normal levels

hypothyroidism

Cretinism to little thyroxin

Some affect fat deposits in the lower extremities

Hormone disorder Diabetes mellitus (I) Not enough Insulin Type I

Addison's Disease Addison's disease is a chronic condition that results when the adrenal glands are unable to produce enough of certain important hormones. This can lead to fatigue, low blood pressure, loss of appetite, and darkening of the skin. Cortisol and aldosterone deficient

Increased levels of Parathyroid hormone -calcium

Estrogen decificency

Testosterone differences

Gynecomastia / estrogen

Oxcitocin

Cushing's syndrome occurs when your body is exposed to high levels of the hormone cortisol for a long time

Cat endocrine disorders