Endocrine System Flashcards
What are 5 functions of the endocrine system?
- Differentiation of the reproductive and central nervous system fetus
- Stimulation of sequential growth and development
- Coordination of the male and female reproductive
- Maintenance of an optimal internal environment
- Initiation of corrective and adaptive responses
The endocrine system is a system of ___
Glands
What is the endocrine system stimulated by?
-Central Nervous System
-Physiologic state
____ are produced, secreted, and sent to the site of action
Hormones
____ are highly specific to each hormone
Receptors
____ refers to the “fit” of the receptor and the ligand
Specificity
Receptors and ligands are similar to a ___ and ___ mechanism
Lock and key
_____ is the strength of the attraction between the ligand and the receptor
Affinity
___ ____ is the production of more receptors when more hormone is needed
Up-regulation
With down-regulation, less _____ are expressed so there is less protein and less action
Receptors
____ is when the presence of one hormone permits or impacts the effectiveness of another hormone (ex: high thyroid hormone makes more receptors for epinephrine)
Permissiveness
Hormones are made in one place and released into the ____ where they can travel to a distant cell where they have their action
Bloodstream
There are ___ soluble and ____ soluble hormones
Water and lipid
Hormone release is controlled via ___ ___
Feedback loops
With a ___ feedback loop, hormone release is inhibited by some other action or substance
Negative
One example of a negative feedback loop is ____, in which high levels shut off additional production
Cortisol
With a ____ feedback loop, something stimulates the release of more hormone
Positive
One example of a positive feedback loop is ____ release during breastfeeding; the pituitary releases it and stimulates milk production and so as long as the baby keeps suckling, it will continue to be released
Oxytocin
Mechanism of the physiological axis:
The hypothalamus stimulates the pituitary gland which stimulates either the thyroid, adrenal, or gonad gland
The ____ links the brain to the endocrine system and the rest of the body
Hypothalamus
The hypothalamus is important for ___ ___ ___ function and also provides feedback and produces hormones
Autonomic nervous system
____ will stimulate the anterior pituitary gland
Neurohormones
The formal endocrine glands include…
-Pituitary (anterior and posterior)
-Thyroid
-Adrenals
-Gonads
-Endocrine pancreas
Hormones released by the anterior pituitary (adenohypophysis) include…
-ACTH
-TSH
-FSH
-LH
-Prolactin
-Growth hormone
-Melanocyte-stimulating hormone
-Lipotropin
-Endorphins
Hormones released by the posterior pituitary (neurohypophysis) gland:
-Oxytocin
-Arginine
-Vasopressin
Hormones released by the thyroid gland:
-Thyroxine (T4)
-Triiodothyronine (T3)
Mechanism of the hypothalamus-pituitary-thyroid (HPA) axis:
-The hypothalamus secretes TRH
-TRH stimulates TSH production and release
-TSH stimulates T3 and T4
Thyroxine (T4) makes up ___% of circulating hormone and will be converted to T3
90
Triiodothyronine (T3) is ___ ___
Biologically active
___% of triiodothyronine (T3) is released from the endocrine gland, and the remaining is converted from T4 in the periphery
15%
What are 4 functions of the thyroid hormone?
- Increases cellular metabolism
- Increases blood pressure maintenance
- Some growth functions (skeletal)
- Temperature maintenance (primarily increases)
Adrenal glands are located above the ___ on either side
Kidneys
Adrenal glands get stimulus from the ____
Pituitary
The adrenal glands are a very ____ structure
Vascular
The adrenal gland is broken up into different ____ that make different hormones
Zones
The ____ is the outer layer of the adrenal gland
Cortex
The cortex of the adrenal gland contains the ___ ____, which is the outermost layer
Zona glomerulosa
The zona glomerulosa produces mineralocorticoides like ____
Aldosterone
The cortex also contains the ___ ____ (one layer in from the glomerulosa)
Zona fasiculata
The zona fasiculata produces things like ____, which helps with low blood pressure and also regulates the autonomic nervous system
Cortisol
The ___ ___ is the next innermost layer
Zona reticularis
The zona reticularis produces ___ ___
Androgenous steroids (sex hormones)
____ are produced in the medulla
Catecholamines
The ___ axis functions in the production of cortisol
HPA
Gonads are very important for ___ ___
Reproductive function
In the HPA axis, the hypothalamus is ____, the pituitary is ____ and the thyroid, adrenal, and gonal are ____
Tertiary, secondary, primary
Syndrome of ____ ___ ____ causes increased secretion of the hormone which leads to excess water retention which leads to hyponatremia and hypervolemia
Inappropriate antidiuretic hormone
Syndrome of inappropriate antidiuretic hormone is caused by ____ ____ dysfunction
Posterior pituitary
Syndrome of inappropriate antidiuretic hormone can be caused by…
-Tumors
-Head trauma
-Medications
____ ___ is caused by decreased posterior pituitary function
Diabetes Insipidus
What are the two types of diabetes insipidus?
-Neurological DI
-Nephrogenic DI
Neurological diabetes insipidus can be seen in people with high ____ consumption
Alcohol
Nephrogenic diabetes insipidus can be caused by poor binding of receptors and this can be seen with ___ ___
Renal transplant
With diabetes insipidus, people don’t have enough ___ ___ ____ which leads to too much water being excreted, highly concentrated blood, and hypernatremia
Antidiuretic hormone
What hormones are produced by the anterior pituitary gland?
-ACTH
-TSH
-FSH
-LH
-Prolactin
-Growth hormone
-
With ____, there is too much production of thyroid hormones which ramps up the metabolic rate and oxygen consumption
Hyperthyroidism