Endocrine System Flashcards
function 1
Encomposes a group of tissues that release hormones circulation for travel to and action on
distant targets
function 2
Endocrine tissue is typically a ductless gland (into
e.g.pituitary , thyroid) that releases its hormones into
capillaries that permeate the tissue
function 3
These glands are richly supplied with blood
function 4
Hormones control or regulate a multitude of biologic
tissue processes in virtually all tissues
act on their target cells receptors located on the cell surface; e.g. by binding adrenocorticotropic (ACTH) from the pituitary, insulin to hormone hormone (PTH)
Protein /Polypeptide Hormones
derivatives of cholesterol and include products of the adrenal cortex, ovaries, and testes as well as the related molecule, Vitamin D - are rapidly synthesized from cholesterol by a series of enzymic reactions and stored intracellularly in the tissue of origin
Steroid Hormoes
made by chemical modification of amino acids, mainly tyrosine
Modified Amino Acid Hormones
- link the nervous system to the endocrine system via
the pituitary gland - responsible for the regulation of certain metabolic
processes and other activities of the autonomic
nervous system
Hypothalamus
stimulates ACTH release
(adenohypophysis)
Corticotropin-RH
stimulates FSH, LH release
(adenohypophysis)
Gonadotropin-RH
stimulates GH release
(adenohypophysis)
Growth Hormone-RH
somatostatin; inhibits GH release
(adenohypophysis)
GH-inhibiting
hormone
stimulates TSH release
(adenohypophysis)
Thyrotropin-RH
dopamine; Inhibits prolactin release
(adenohypophysis)
Prolactin-IH
Neurohypophysis Hormones
stimulates uterine contraction, milk
letdown (uterus, mammary glands)
Oxytocin
Neurohypophysis Hormones
vasopressin; conserves water, reduces urine volume (kidney); constricts vessels to raise blood pressure (arterioles)
Antidiuretic hormone (ADH)
- is anatomically and functionally related to the
hypothalamus. - an essential gland of the body and sometimes
referred to as the “master gland”, because it can
control several of the other hormone glands. - is a bean-sized organ suspended from the
hypothalamus by a stem called the infundibulum
(pituitary stalk).
Pituitary Gland - Hypophysis
2 lobes
posterior pituitary, anterior pituitary
(neurohypophysis) composed of neural tissue
posterior pituitary
(adenohypophysis) composed of glandular tissue.
anterior pituitary
between the posterior and
anterior lobes, synthesizes and secretes
melanocyte-stimulating hormone (MSH).
intermediate lobe
Adenohypophysis Hormones
stimulates cortical development, glucocorticoid release (adrenal cortex)
Adrenocorticotropic hormone (ACTH)
Adenohypophysis Hormones
stimulates follicular development (ovary), sperm development (testes)
Follicle-stimulating hormone (FSH)
Adenohypophysis Hormones
lutropin; stimulates ovulation,
development of corpus luteum,
secretion by corpus luteum (ovary),
secretion of androgens (testes)
Luteinizing hormone (LH)
Adenohypophysis Hormones
somatotropin; Promotes growth in immature animals; metabolic effects on carbohydrate, lipid,
protein metabolism in adults
Growth hormone (GH)
Adenohypophysis Hormones
stimulates release of thyroid hormones (follicular cells of thyroid gland)
Thyroid stimulating hormone (TSH)
Adenohypophysis Hormones
promotes lactation (mammary gland), maternal behavior (central nervous system)
Prolactin (PRL)
- are small, triangular-shaped glands located on top
(cranial) on both kidneys. - produce hormones that help in regulating
metabolism, immune system, blood pressure, and
responses to stress, and other essential functions.
Adrenal gland
secretes steroid hormones
outer cortex
secretes adrenaline
inner medulla
Adrenal Cortex Hormones
essential for normal response to stress; important roles in protein, carbohydrate metabolism
(multiple organs including liver)
Glucocorticoids
Adrenal Cortex Hormones
aldosterone; conserve Na, eliminate K (kidney)
Mineralocorticoids
Adrenal Medulla Hormones
augments sympathetic response to stress by
actions on several organs
Epinephrine, Norepinephrine
is a butterfly-shaped organ located in the base of the
neck.
Thyroid Gland
2 major types of cells of TG
follicular cells produce hormones and parafollicular cells
responsible in controlling metabolism
follicular cells produce hormones
produce hormone responsible in calcium (Ca) regulation.
parafollicular cells
Thyroid Follicular Cells
increases oxygen consumption, ATP generation
(almost all cells)
Triiodothyronine (T3)
Thyroid Follicular Cells
promotes calcium retention (bone)
Thyroxine (T4)
Thyroid Parafollicular Cells
promotes calcium retention (bone)
Calcitonin
promotes increase in plasma calcium, reduction in plasma phosphate (bone, kidney)
Parathyroid hormone
involves a response that is the reverse of the change detected (it functions to reduce the change)
Negative Feedback
involves a response that reinforces the change detected (it functions to amplify the change)
Positive Feedback
