A&P Chapter 17- Endocrine System

Aldosterone

"salt-retaining hormone" which promotes the retention of Na+ by the kidneys. na+ retention promotes water retention, which promotes a higher blood volume and pressure

Transcription

(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA

Translation

(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm

Toxic goiter

(graves disease)- antibodies mimic TSH, increase TH, exophthalmos (bulgiing of the eyeballs)

Ovary

(vertebrates) one of usually two organs that produce ova and secrete estrogen and progesterone

Lipid metabolism

- greater energy yield than from glucose or protein catabolis

Mineralocorticoids

1 of 3 the major groups of steroid hormones produced by the adrenal cortex; stim: by ACTH and low blood volume; func: reabsorb NA+ & water, including aldosterone.

Pituicytes

AKA glial cells specialized neuroglia

Lipoxygenase

Enzyme that converts arachidonic acid to leukotriene precursors

Pineal gland

Secretes melatonin

Cholecalciferol

Vitamin D3

Paracrines

chemical messengers, exert effect on nearby cells

IGFs

insulin-like growth factors (somatomedins)- liver, other tissues

Renal calculi

kidney stones

Stage of exhaustion

third stage of the GAS during which the body depleates its resources in responding to an ongoing stressor

Thyroglobulin

thyroid hormnone synthesis involves secretion of a glycoprotein called_____ by the follicular cells

TH

thyroid hormone (t3 and t4 collectively)- thyroid

TSH

thyroid stimulating hormone (thyrotropin)- anterior pituitary metabolic effects

TRH

thyrotropin releasing hormone- hypothalamus

T4

thyroxine (tetraiodothyronine)- thyroid

Protein kinases

transfer phosphates from ATP to protein (phosphorylation)

TH Synthesis

1. cells of thyroid follicule begin process by absorbing iodine ions from blood (at same time) 2. follicle cells synthesize throglobin and release by exocytosis from apical surface into lumen 3. an enzyme at cell surface adds iodine to tyrosines, some of which receive one iodine and become monoiodtyrosine and some receive two and become diiodotyrosine. The tyrosines link to each other 4. When follicle cells receive TSH they absorb Tg by pinocytosis a TH gets liberated 5. TH is release into capillaries, in blood it binds to transport proteins that carry it to target cells

Three interactive effects of hormones

1. synergistic 2. permissive 3. antagonistic

The half life of GH

6-20 minutes

Epinephrin

A catecholamine secreted by the adrenal medulla in response to stress preparing the body for "flight or fight" (trade name Adrenalin)

Basophil

A circulating leukocyte that produces histamine.

Diabetes mellitus

A condition in which the body is unable to produce enough insulin, the hormone required for the metabolism of sugar Hyposecretion or inaction of insulin Disruption of carbohydrate, fat, and protein metabolism Polyuria, polydipsia, polyphagia, hyperglycemia, glycosuria, ketonuria

Calmodulin

A cyoplasmic Ca2+-binding protein. Calmodulin is particularly important in smooth muscle cells, where binding of Ca2+ allows calmodulin to activate myosin light-chian kinase, the first step in smooth muscle cell contraction.

Prostaglandins

A group of bioactive, hormone-like chemicals derived from fatty acids that have a wide variety of biological effects including roles in inflammation, platelet aggregation, vascular smooth muscle dilation and constriction, cell growth, protection of from acid in the stomach, and many more.

Estrogens

A group of sex hormones found more abundantly in females than males. They are responsible for female sexual maturation and other functions.

Parathyroid Hormone

A hormone of the parathyroid gland that regulates the metabolism of calcium and phosphorus in the body

Erythropoietin

A hormone produced and released by the kidney that stimulates the production of red blood cells by the bone marrow.

Leptin

A hormone produced by adipose (fat) cells that acts as a satiety factor in regulating appetite.

Progesterone

A hormone produced by the ovaries which acts with estrogen to bring about the menstral cycle.

Calcitriol

A hormone produced from vitamin D that acts in essentially the same manner as parathyroid hormone.

Cortisol

A hormone secreted by the adrenal glands, which sit on top of the kidneys; it is secreted in response to stress and helps trigger the changes of the fight or flight response, including increased blood glucose, altered immune function, and reduction in nonessential body functions.

Transport protein

A membrane protein, specifically a transport protein, that has a hydrophilic channel that certain molecules or atomic ions use as a tunnel.

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

Stress

A physical and mental response to a challenging or threatening situation.

Calcitonin

A polypeptide hormone especially from the thyroid gland that tends to lower the level of calcium in the blood plasma

Glucagon

A protein hormone secreted by pancreatic endocrine cells that raises blood glucose levels; an antagonistic hormone to insulin.

Inhibin

A protein hormone secreted by sustenacular cells of the testes that acts to inhibit the release of FSH and LH from the anterior pituitary.

Cyclic AMP

A second messenger derived from ATP and triggers specific cellular changes in metabolic regulation

Cyclic amp

A second messenger derived from ATP and triggers specific cellular changes in metabolic regulation

Inositol triphosphate

A second messenger derived from membrane phospholipids and triggers the release of CA2+ from the endoplasmic reticulum

Diacylglycerol

A second messenger produced by the cleavage of a certain kind of phospholipid in the plasma membrane.

Infundibulum

A stalk that attaches the pituitary gland to the hypothalamus.

Transport proteins

A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane.

mRNA

A type of RNA, synthesized from DNA, that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein.

Cholesterol

A type of fat made by the body from saturated fat; a minor part of fat in foods.

Communication by nervous and endocrine system

A) a neuron has a long fiber that delivers its neurotransmitter to the immediate vicinity of its target cells. B) endocrine cells secrete a hormone into the bloodstream. At a point often remote from its origin, the hormone leaves the bloodstream and enters or binds to its target cells

Anterior pituitary

AKA adenohypophysis Gland in the brain that releases many hormones, including growth hormone, luteinizing hormone, thyroid-stimulating hormone, adrenocorticotropic hormone, and follicle-stimulating hormone

Corticosteroids

AKA corticoids Steroid hormones secreted from the adrenal cortex. The two major classes are the mineralocorticoids and glucocorticoids. Aldosterone is the principal mineralocorticoid, and cortisol is the principal glucorcorticoid.

Posterior pituitary

AKA posterior lobe or neurohypohysis This part of the pituitary does not produce hormones, but stores and releases oxytocin and ADH.

Pituitary gland

AKA: hypophysis-The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands. -suspended by infundibulum -housed in sella turica of sphenoid bone -adenophypophysis=anterior pituitary -neuroohyphysis=posterior pituitary

Zona glomerosa

Adrenal cortex outer zone

Adrenal medulla

An endocrine organ that secretes epinephrine and norepinephrine in concert with the activation of the sympathetic nervous system; for example, in response to stress

Thymus

An immune organ located near the heart. The thymus is the site of T cell maturation and is larger in children and adolescents.

Cholecystokinin

An intestinal hormone that stimulates the gallbladder to release bile

Pancreas

An organs in the abdominal cavity with two roles. The first is an exocrine role: to produce digestive enzymes and bicarbonate, which are delivered to the small intestine via the pancreatic duct. The second is an endocrine role: to secrete insulin and glucagon into the bloodstream to help regulate blood glucose levels.

Gonadotropins

Anterior pituitary topic hormones FSH (follicle stimulating hormone) and LH (luteinizing homeon) that stimulates the gonads (testes and ovaries) to produce gametes and to secrete sex steroids.

ADH

Antidiuretic hormone (arginine vasopressin)- posterior pituitary increases water retention by kidneys; vasoconstrictor at high concentrations

Transcriptional activator

As substrate for an enzyme increases, the amount of enzyme present can be increased to facilitate catalysis. This would be best achieved by

Hypothalamo-pituitary-thyroid axis

Axons extend to posterior pituitary, release ADH, and oxytocin

Prostacyclins

Biologically active substances produced by blood vessel walls that inhibit platelet aggregation and there fore blood clotting, dilate blood vessels and reduce blood pressure.

Monamine

Blocks the action of monoamine oxidase in the brain which then allows the accumulation of monoamines which can alter mood norepinephrine

Chromaffin Cells

Cells are modified postganglionic sympathetic neurons that become secretory Typically stain brown

Keratinocytes

Cells made of Keratin, comprise of 95% of the Epidermis; move up thru the layers

Acinar

Cells that make up exocrine galnds, adn that secrete their products into ducts. For example, in the pancreas, acinar cells secrete digestive enzyme; in the salivary glands, acinar cells secrete saliva.

Membrane proteins

Channels, Recogniton, Support, Receptors, Cell attachment

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

Hormones

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Leukotrienes

Chemical substances that contribute to anaphylaxis; released by the immune system in allergic reactions.

Pancreatic islets

Control blood sugar levels and glucose metabolism

Dehydroepiandrosterone

DHEA precursor of testosterone; indirectly promotes growth of bones, , pubic and axillary hair, apocrine glands, and fetal male reproductive tract; stimulates libido; targets- bone, muscle, integument, brain, many other tissues; source- adrenal cortex

Sustentacular cells

Developing sperm cells are protected by a blood-testis barrier formed by

Theca

Develops a rich supply of blood vessels and collaborates with follicle cells to secrete sex hormones, especially estrogen

Gastrin

Digestive hormone that stimulates sustained secretion of gastric juice from the stomach

Endocrine glands

Ductless or tubeless organs or groups of cells that secrete hormones directly into the bloodstream

Signal amplification

Enzyme cascades amp the cell's response to a signal. At each step in the cascade, the number of activated products is much greater than the prev step

EPO

Erythropoietin- kidney, liver

FSH

Follicle stimulating hormone-anterior pituitary, stimulates egg or sperm production

Protein synthesis

Forming proteins based on information in DNA and carried out by RNA

Sympathetic ganglion

Ganglion receives preganglionic sympathetic fibers from T1 to L1-2 and innervates smooth muscle, cardiac muscle, glands, head, thoracic viscera, and blood vessels of the body wall and limbs.

Communication within the body

Gap junctions paracrine hormones neurotransmitters hormones

Carbohydrate metabolism

Glycogenesis -- (glycogen synthesis) is the building of glycogen using two main enzymes

Fenestrated capillaries

Have pores that allow small molecules and some proteins to diffuse. They are found in the endocrine system, intestines, and pancreas

Type II diabetes

High blood sugar levels due to lack of insulin production in the pancreas. A noninsulin dependent disease known as adult onset diabetes.

Type I diabetes

High blood sugar levels due to lack of insulin prodution in he pancreas. An insulin dependent disease. Can delay lactogenesis II

Somatostatin

Hormone inhibits glucagon release and pancreatic exocrine secretions synonym for growth hormone

Thymopoietin

Hormone secreted by the thymus, thought to stimulate the production of T-cells.

Steroid

Hydrocortisone, prednisone, dexmethasone; indicated for hormone replacement, severe rheumatoid arthritis, and autoimmune disorders; adverse reactions: emotional liability, impaired wound healing, skin fragility, abnormal fat disposition, hyperglycemia, hirsutism, moon face, osteoporosis; wean slowly; monitor serum potassium, glucose and sodium; weigh daily and report >5lb/week; administer with antiulcer drugs; prevent injurys; monitor BP and HR

Adrenogenital syndrome

Hypersecretion of androgens from the adrenal gland which leads to development of male sex characteristics

Cushing's disease

Hypersecretion of glucocorticoids causing upper body obesity, moon face, poor skin integrity, osteoporosis, hyperglycemia, hypernatremia,hypokalemia, hirsutism, amenorrhea, elevated triglycerides, hypertension, and immunosuppression

Insulin-like growth factor I

IGF-I Released by Liver, circulate in blood and directly stimulates bone and cartilage growth

Eicosanoids

Important in regulating many physiologic functions such as inflammation, pain perception, blood flow and smooth muscle contraction

Up-regulation

In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of target cells will specify the synthesis of more receptors on the surface of the cells of the target organ.

Phosphodiesterase

Inhibit cyclic adenosine monophosphate phosphodiesterase, leading to increased levels of adenosine monophosphate within the cells.

Testis

Interstitial cells make testosterone/sperm when stimulated by FSH and LH from the pituitary gland.

Electrolyte balance

Involves keeping osmolarity stable by adjusting the fluid in the extracellular compartment

Neuroendocrine reflexes

Is initiated by the stimulation of sensory neurons, that cause of release of neurohormone from the neurosecretory cells, it id controlled by a simple neural reflex. (sensory impulses, hormonal signal, physiological response) the secretion of prolactin is controlled by this reflex. suckling stimulates the sensory fibers in the breast and they send nerve impulses to the hypothalamus.

LH

Luteinizing hormone- anterior pituitary stimulates secretion of estrogen and progesterone or testosterone

Testosterone

Male hormone

Zona fasciculata

Middle layer; secretes cortisol in response to ACTH (glucocorticoids).

Synergism

More than one hormone produces the same effects on a target cell

Cyclooxygenase

NSAIDs help relieve inflammation by blocking the effect of ____ on arachadonic acid

NE

Norepinephrine- adrenal medulla

Permissive effects

One hormone enhances the target organ's response to a second later hormon

Peptide YY

PYY regulates digesta flow and enhances absorption

Zona reticularis

Part of the adrenal cortex are androgens made

Glucocorticoids

Produced by adrenal cortex; is 1 of 3 corticosteriods (corticoids); increase blood sugar levels during times of stress.

Mechanisms of GH-IGF Action

Protein synthesis lipid metabolism Carbohydrate mechanism Electrolyte balance

G-proteins

Proteins that are activated by exchanging bound GDP for bound GTP (and thus also known as GTP-binding proteins).

Endrocrine system

Regulates body activities through hormones

SAIDs

SAIDS: steroids; inhibit inflammation; block paracrine messengers; Cushing syndrome side effect

Stage of resistance

Second stage of the GAS, during which the body adapts to and uses resources to cope with a stressor

Hypophyseal portal system

Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from hypothalamus to anterior pituitary gland.

Second messengers

Small, non-protein water soluble molecules or ions that send messages throughout the cells by diffusion.

Eicosanoid synthesis

Stimulus activates the enzyme phospholipase A2; Arachidonic acid splits off from membrane phospholipids; Those metabolized by either cyclooxygenase or lipoxygenase; leads to formation of leukotrienes and prostaglandins

Hormone interaction

Synergistic Permissive Antagonistic

Stress response

The body's initial reaction to stress.

General adaptation

The body's response to an increased demand. The first stage is initial adaptive response aka fight or flight mechanism. If it is prolonged maladaptive responses can occur

General Adaptation Syndrome

The body's response to an increased demand. The first stage is initial adaptive response aka fight or flight mechanism. If it is prolonged maladaptive responses can occur: alarm reaction; stage of resistance, stage of exhaustion

Protein sparing effect

The consumption of sufficient kilocalories in the form of carbohydrate and fat, which protect protein from being used as energy before other protein related functions are met

Estradiol

The granulosa cells of developing follicles secrete this

Negative feedback inhibition

The pituitary stimulates another endocrine gland to secrete its hormone, and that hormone feeds back to the pituitary or hypothalamus and inhibits further secretion of the pituitary hormone. Ex.) the Thyroid hormone inhibits TRH and TSH secretion

Unmyelinated nerve fiber

The posterior lobe of the pituitary gland consists of

Thymulin

Thymus hormone responsible for T-cell differentiation and enhancement of T and NK cell actions

T3

Triiodothyronine- thyroid

Follicular cells

What cells of the thyroid gland secrete T3 and T4

Synergistic effects

When the effects of two factors working together have more impact than either would working alone

Arachidonic acid

______ is the precursor for prostaglandins, leukotrienes, and thromboxanes.

Acidophil

`bacteria that survive in a pH below 6.0 and make foods such as sour cream and yogurt

Pheochromocytoma

a benign tumor of the adrenal medulla that causes the gland to produce excess epinephrine

Osteocalcin

a calcium-binding protein in bones, essential for normal mineralization

Angiotensinogen

a circulating protein produced by the liver from which angiotensin I is cleaved by the action of renin

Pituitary dwarfism

a condition of congenital hyposecretion of growth hormone that slows growth and causes short, yet proportionate, stature (not affecting intelligence); often treated during childhood with growth hormone; other forms of dwarfism are most often caused by genetic defects

Hepcidin

a hormone produced by the liver that regulates iron balance.

Isthmus

a narrow bridge of tissue in the thymus connecting two winged lobes

Norepinenphrin

a neurotransmitter whose abnormal activity is linked to depression and panic disorder

Adrenal gland

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

Adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

Hypersecretion

abnormally increased secretion

Antagonistic

acting in opposition to another

Corticosteron

adrenal gland (cortex) - glucocorticoids - targets most cells; accelerate glucose synthesis and glycogen formation, show anti-inflammitory effects, inhibit release of histamines

ACTH

adrenocorticotropic hormone (corticotropin)-anterior pituitary stress response; stimulates secretion of corticosteroids by adrenal cortex

Myxedema

advanced hypothyroidism in adulthood

Peptide hormones

amino acid polymers, chain of amino acids, they are water solubluable

Hashimoto's thyroiditis

an autoimmune disease in which the body's own antibodies attack and destroy the cells of the thyroid gland

Graves' disease

an autoimmune disorder that is caused by hyperthyroidism and is characterized by goiter and/or exophthalmos

Glucose sparing effect

as circulating fatty acid levels rise, many tissues stop breaking down glucose and start breaking down fatty acids to generate atp

ANP

atrial natriuretic peptide- Heart

Bound hormone

attached to carrier

Alkalosis

buildup of excess base in the body fluids

Chromophobe

cells of the adenohypophysis may have undergone degranulation

Interstitial cells

cells which in the female are located between the ovarian follicles and in the male are located between the seminiferous tubules of the testes

C cells

clear cells or parafollicular cells Cell type of the thyroid gland; also called parafollicular cells; situated between or within the walls of follicles; responsible for the production of calcitonin.

Tetany

constant muscle contraction

Paraventricular nuclei

controls rate at which posterior pituitary releases vasopressin, lie in the walls of the third ventricle

CRH

corticotropin-releasing hormone- hypothalamus

Transport maximum

creates a limit for reabsorption, maximum amount of substance that can be absorbed at a given time, limited by the # of transport proteins present

Hyposecretion

deficient hormone production by an endocrine gland

Hypokalemia

deficient potassium in the blood

DHEA

dehydroepiandrosterone- adrenal cortex

Nervous system Internal communication

electrical impulses and neurotransmitters, local, specific effects, reacts, stops, and adapts quickly

Thyroid gland

endocrine gland located below the voice box; it produces hormones which control metabolism

Acromegaly

enlargement of the extremities

Endemic goiter

enlargement of the thyroid gland occurring in certain regions and peoples where there is a lack of iodine in the diet

Thromboxanes

facilitate the clumping of platelet and constrict blood vessels, Antagonists in hemostasis

Parathyroid

for glands embedded in the thyroid; secretes parathormone; controls announces level of calcium and phosphate (which influence levels of excitability)

Calcidiol

form of vitamin D is measured in the blood

Gluconeogenesis

formation of glucose from noncarbohydrate sources

Unbound hormone

free unattached very small fraction, able to exit blood, bind to receptor

The body's four principle avenues of communication from cell to cell

gap junction, neurotransmitters, paracrines, hormones

GnRH

gonadotropin-releasing hormone-hypothalamus

What are both endocrine and exocrine

gonads; exocrine are eggs and sperm; endocrine Ovaries:Estradiol Progesterone Inhibin Testes: Testosterone Inhibin

GH

growth hormone (somatotropin)- anterior pituitary acts on body tissues; stimulates liver to produce IGF (somatomedins) - affects protein synthesis, lipid metabolism, carbohydrate metabolism, electrolyte balance

HGRH

growth hormone-releasing hormone- hypothalamus

Organs that have endocrine functions

heart: Atrial natriuretic peptide (ANP) decreases BP skin: Vitamin D (calcidiol precursor) made by keratinocytes liver: Erythropoietin (EPO) stimulates RBC production Angiotensinogen (angiotensin I precursor) Calcidiol (calcitriol precursor) Insulin-like growth factor (IGF-1) mediates action of GH Hepcidin increases intestinal absorption of iron Kidneys: EPO (about 85% of that made) Angiotensin I (converted to angiotensin II in lungs; increases BP), Calcitriol promotes calcium absorption by small intestine Stomach and small intestine: Enteric hormones coordinate digestive gland secretion Placenta:Estriol and estradiol, Progesterone Adipose tissue: Leptin slows appetite Osseous tissue:Osteocalcin secreted by osteoblasts increases number of pancreatic beta cells, pancreatic output of insulin, and insulin sensitivity of body tissues; inhibits weight gain and onset of type 2 diabetes mellitus

Second messenger pathway

hormone binds to receptor-->g protein does two things; 1. opens cell membrane calcium channels, 2. releases calcium from endoplasmic reticulum-->increase in intracellular calcium-->calcium binds to calmodulin-->physiological action results

Ghrelin

hormone secreted by empty stomach; sends "I'm hungry" signals to the brain

Inhibiting hormones

hormone secreted by the hypothalamus that can suppress secretion of hormones by the anterior pituitary

Renin

hormone secreted by the kidney; it raises blood pressure by influencing vasoconstriction (narrowing of blood vessels)

Catecholamine

hormones secreted by the adrenal medulla that affect the sympathetic nervous system in stress response

Enteric hormones

hormones secreted by the stomach and small intestines coordinate digestive motility and glandular secretion.

Insulin like growth factors

hormones that stimulate general body growth and regulate various aspects of metabolism

Releasing hormones

hormones that stimulate other glands to release their hormones

Corticosterone

hormones which works by activation of genes, stimulate fat and protein catabolism, gluconeogenesis; anti-inflammatory

Endocrine system internal communication

hormones, more general, widespread effects, slower, to react, stop, or adapt (release into bloodstream)

Natriuretic peptides

increase GFR, increase urine volume and lower blood pressure

Angiotensin

increases blood pressure by stimulating kidneys to reabsorb more water and by releasing aldosterone

Angiotensin II

increases blood pressure by stimulating kidneys to reabsorb more water and by releasing aldosterone

Diabetes insipidus

insufficient production or utilization of the antidiuretic hormone Decreased secretion of ADH Major polyuria and dehydration NOT increased glucose in blood or urine

Androgens

male sex hormones

Tyrosine

melanin is made up of what Amino Acid

Katoacidosis

metabolic acidosis due to increase in ketones as fat and protein are broken down

Thyroid follicles

microscopic spherical sacs that make up most of the thyroid gland

Supraoptic nuclei

named for location above optic chiasm where ADH comes from

NSAIDs

nonsteroidal anti-inflammatory drugs

Addison's disease

occurs when the adrenal glands do not produce enough of the hormones cortisol or aldosterone

Antagonistic effects

one hormone opposes the action of another

Target organs

organs that respond to a particular hormone

OT

oxytocin- posterior pituitary labor, let-down, semen propulsion Positive feedback so can't stop labor

PTH

parathyroid hormone (parathormone)- Parahthyroids

Hypothalamo-hypophyseal tract

portal between hypothalamus and pituitary

Chromaffin cells

preganglionic sympathetic fiber

Protein Structure

primary, secondary, tertiary, quaternary

Prostycyclin

produced by walls of BV, where it inhibits blood clotting and vasoconstriction

PIH

prolactin inhibiting hormone (dopamine)- hypothalamus

PRL

prolactin- anterior pituitary stimulates milk synthesis or testicular sensitivity to LH

Mechanisms of GH-IGF action

protein synthesis, lipid metabolism, carbohydrate metabolism, electrolyte balance

Gap junction

provide cytoplasmic channels between adjacent animal cells

Involution

reduction in size of an organ or part (as in the return of the uterus to normal size after childbirth)

Osmoreceptors

respond to osmolarity of blood: water homeostasis

Calorgenic effect

responsible for strong,immediate, short lived increase in rate of cellular metabolism

Exocrine glands

secrete chemical substances into ducts that lead either to other organs or out of the body

Alpha cells

secrete glucagon, Stimulates gluconeogenesis and glycogenolysis

Beta cells

secrete insulin, Stimulates cellular absorption of glucose and amino acids Promotes glycogen synthesis

Delta cells

secrete somatostatin, Inhibits glucagon and insulin secretion

Thymosin

stimulates the maturation of lymphocytes into T cells of the immune system

Alarm reaction

stressor triggers increased activity of the sympathetic nervous system

Endocrinology

study of the endocrine glands

Monoamines

synthesized from amino acids by removal of the -COOH group. They retain the -NH2 (amino group), hence their name. Some monoamine neurotransmitters are epinephrine, norepinephrine, dopamine, histamine, ATP, and serotonin. The first three of these are subclass catecholamines

Down-regulation

target cells lose receptors in response to high hormone levels

Protein Synthesis

the formation of proteins by using information contained in DNA and carried by mRNA

Primary capillaries, portal venules, secondary capillaries

the hypo portal system consists of a network of _ _ in the hypothalamus, a group of small veins called _ _ that travel down the stalk and a compile of _ _ in the anterior pituitary

Granulosa cells

the majority of the cells surrouding an oocyte in a follicle. Granulosa cells secrete estrogen during the follicular phase of the ovarian cycle (before ovulation).

Adrenal cortex

the ourter part of the adrenal gland that secretes many hormones, including cortisone and aldosterone