Kines 203 L10 Endocrine System

endocrine system

a widely distributed group of glands that secrete hormones to maintain homeostasis

the three glands in the cranial cavity

hypothalamus, pineal gland, and pituitary gland

hypothalamus

really part of the nervous system but it controls the pituitary gland

anterior lobe of the pituitary gland

releases six hormones

posterior lobe of the pituitary gland

releases two hormones

pineal gland

located in the brain and releases melatonin

thyroid gland

primarily releases triiodothyronine (T3) and thyroxine (T4)

parathyroid glands

secrete parathyroid hormone

calcitonin or calcium metabolism

thyroid and parathyroid glands work together to regulate what

thymus gland

located on top of the heart right behind the breastbone; secretes thymosin

pancreas

located in the epigastric region; releases glucagon and insulin which regulate glucose metabolism in the body

adrenal glands

secrete cortisol, aldosterone, norepinephrine, and epinephrine; typically secreted during stressful situations (fight or flight response)

ovaries

produce estrogen and progesterone; located int eh right and left inguinal regions

testes

produces testosterone; located in the scrotum

production of hormones

controlled by negative feedback where the hormone itself regulates future production

hormones

affect growth, metabolism, behavior, and reproduction

steroid hormones

lipid-based and produced by the sex glands and outer adrenal glands

amino acid hormones

protein-based and include the remaining endocrine glands

problems with hormone secretion, problem with the target tissue, or problems with the endocrine glands themselves

what are the three main causes when clinical conditions arise in the endocrine system

hypersecretion

when too much of a hormone is being secreted

hyposecretion

when not enough of a hormone is being secreted

six hormones released by the anterior lobe of the pituitary gland

GH (growth hormone), TSH (thyroid stimulating hormone), ACTH (adrenocorticotropic hormone), FSH (follicle stimulating hormone), LH (luteinizing hormone), PRL (prolactin)

two hormones released by the posterior lobe of the pituitary gland

antidiuretic hormone (ADH) and oxytocin

antidiuretic hormone (ADH)

when this hormone is released, it causes the kidneys to conserve water which happens through vasoconstriction of the blood vessels in the area

oxytocin

acts primarily on the female reproductive system by stimulating uterine contractions which initiates labor; after the baby is born is promotes “milk let down”

milk let down

when the hormone oxytocin kicks into gear and the mammary glands int he ducts in your breast, relax, to let down milk for feeding

pitocin

a medication given to women to stimulate labor when it’s not progressing; often used if oxytocin elvels are low and labor is not progressing

T4 and T3

both these hormones contain iodine which is bound to proteins int eh blood via TBG (thyroxine-binding globulin)

parathyroid hormone (PTH)

helps with calcium metabolism by increasing blood calcium levels

outer cortex of the adrenal glands

secretes cortisol, aldosterone, and testosterone

cortisol

decreases inflammation and increases fats and carbohydrates in the blood

aldosterone

helps the kidneys conserve water and sodium and eliminate potassium

testosterone

responsible for the development of secondary male sex characteristics such as muscle hypertrophy, voice deepening, gonads development, sperm production, and increase in hair

inner medulla of the adrenal glands

releases two hormones epinephrine and norepinephrine which are responsible for the fight or flight response

epinephrine

during a stressful situation increases your blood pressure, heart rate, and respiratory rate.

norepinephrine

increases the stress response and can be produces by exercise, adequate sleep, and higher protein diets

pancreatic islets

small clusters of cells that maintain glucose metabolism by releasing insulin and glucagon

insulin

decreases glucose in the body by increasing cellular use

glucagon

increases glucose in the blood by decreasing cellular use

diabetes

happens when a person’s pancreas is malfunctioning and does not secrete insulin or an adequate amount of insulin in response to what a person eats

melatonin

helps with sleep-wake cycles, regulating mood, and sexual development

thymosin

stimulates T cells for immunity

gonads

secrete sex hormones

endocrino

means endocrine gland or system

pituitari

means pituitary gland

hypophysio

means hypophysis

thyro

means thyroid gland

parathyro

means parathyoid gland

adreno

means adrenal gland

adrenocortico

means adrenal cortex

insulo

means pancreatic islets or pancreas

hypersecretion of growth hormone

acromegaly (adults) and giantism (children)

hyposecretion of growth hormone

dwarfism (children)

hypersecretion of antidiuretic hormone

SIADH (syndrome of inappropriate ADH)

hyposecretion of antidiuretic hormone

diabetes insipidus

hypersecretion of aldosterone

aldosteronism

hyposecretion fo aldosterone

addison disease

hypersecretion of cortisol

cushing’s syndrome

hyposecretion of cortisol

addison’s disease

hypersecretion of thyroid hormone

grave’s disease

hyposecretion of thyroid hormone

congenital hypothyroidism

hypersecretion of insulin

hypoglycemia

hyposecretion of insulin

diabetes mellitus

hypersecretion of parathyroid hormone

osteopenia, osteoporosis

hyposecretion of parathyroid hormone

tetany

growth hormone (GH)

released by the anterior pituitary gland, promotes growth of all body tissues

TSH (thyroid-stimulating hormone)

released by the anterior pituitary gland; stimulates the thyroid gland to produce thyroid hormones

ACTH (adrenocorticotropic hormone)

released by the anterior pituitary gland; stimulates adrenal cortex to produce cortical hormones and aids in protecting body is stress situations

FSH (follicle-stimulating hormone)

released by the anterior pituitary gland; stimulates growth and hormonal activity of the ovarian follicles, stimulates growth of testes, and promotes sperm cell development

LH (luteinizing hormone)

released by the anterior pituitary gland; causes development of corpus luteum at the site of ruptured ovarian follicle in female and stimulates testosterone secretion in male

PRL (prolactin)

released by anterior pituitary gland; stimulates milk secretion by mammary glands

T3 and T4

released by thyroid gland; increase metabolic rate and heat production, influencing both physical and mental activities and is required for formal growth

estrogen

released by ovaries; stimulates growth of primary sexual organs and development of secondary sexual characteristics

progesterone

released by the ovaries; prepares uterine lining for implantation of fertilized ovum, aids in maintaining pregnancy, and stimulates development of mammary gland secretory tissue

Adenoma

a tumor of the pituitary glands that often causes the pituitary to increase growth hormone and/or ACTH

signs and symptoms of adenoma

headaches or pressure in the head, vision problems, and hormone hypersecretion

diagnosis of adenoma

CT scan or MRI

giantism

increased growth hormone in children

acromegaly

increased growth hormone in adults

panhypopituitarism or dwarfism

hyposecretion of growth hormone

diabetes insipidus

when the posterior pituitary gland is not releasing antidiuretic hormone (AD) in sufficient quantities and the kidneys can’t conserve water

the telltale signs and symptoms of diabetes insipidus

polyuria and polydipsia (when you are losing lots of water, and get dehydrated and feel very thirsty)

Congenital hypothyroidism

thyroid hormone (T3 and T4) levels are so low when born that they can actually be clinically absent, causing mental retardation, stunted growth, and physical deformities

signs and symptoms of congenital hypothyroidism

lack of weight gain, stunted growth, fatigue, lethargy, poor feeding, thickened facial features, abnormal bone growth, mental retardation, very little crying, excessive sleep, constipation, jaundice, hoarse voice, large tongue, umbilical hernia

myxedema

adult form of hypothyroidism, thought of as an auto-immune disorder

signs and symptoms of myxedema

altered mental status, hypothermia, changes in skin, weight gain, lethargy, dry skin, hair loss, facial swelling

Grave’s disease

an autoimmune disorder that causes increased thyroid hormone production

signs and symptoms of Grave’s disease

weight loss, thinning hair, sweating, shakes, tremors, typically really high respiratory rates, high heart rate, blood pressure increase, irritability, tremor, increase HR, exophthalmos, menstrual cycle irregularities

treatment for Grave’s disease

thyroid removal, radioactive iodine and thyroid hormone suppression therapy

Goiter

the most common thyroid condition and presents with an enlargement of the actual thyroid gland

treatment for goiters

surgically removing the tumor by either removing the tumor off the gland or the whole gland

parathyroid tumors

can cause an increase of calcium in the blood and a decrease in calcium in the skeletal system resulting in the development of kidney stones, osteoporosis, bone pain, and skeletal weakness

Addison’s disease

a hypofunction of the adrenal cortex, which causes a decrease int eh adrenal cortex hormones

treatment of Addison’s disease

cortical hormones

Cushing syndrome

hyperfunction of adrenal cortical hormones which increases the cortex hormones

Diabetes mellitus

pancreatic diabetes

type I diabetes mellitus (T1DM)

pancreatic islets are not making insulin at all, autoimmune destruction of the pancreas, insulin levels are low or absent, usually appears in children and teens, patients usually require insulin

type II diabetes mellitus

don’t make sufficient quantities of insulin, 90% of diabetes cases, heredity predominates, caused by cellular resistance to insulin, usually found in obese people with poor diet and sedentary lifestyle, may or may not require insulin

gestational diabetes mellitus (GDM)

glucose intolerance during pregnancy due to the mother carrying a baby which increases the overall body weight of the mother and stresses the pancreas