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Physiology Lecture Exam > Endocrine > Flashcards

Flashcards in Endocrine Deck (36):
1

Humoral Hormone (mechanism of hormone release):

in response to changing levels of ions or nutrients in the blood

2

Neural (mechanism of hormone release)

stimulation by nerves

3

Hormonal (mechanism of hormone release)

stimulation received from other hormones

4

The hypothalamus controls....?

secretion of hormones which also control the secretion of hormones by the thyroid gland, the adrenal cortex and gonads: in this way the brain controls these endocrine glands.

5

What are the five releasing hormones of the hypothalamus?

1. TRH (thyroid releasing hormone) -----turns on* TSH
2.CRH (corticotropin releasing hormone) --turns on ACTH
3.GnRH (gonadotropin releasing hormone) ---turns on FSH and LH
4. PRF (prolactin releasing hormone) -----turns on PRL
5. GHRH (growth hormone releasing hormone) ----turns on GH

6

What are the two inhibiting hormones of the hypothalamus?

1. PIF (prolactin inhibiting factor) -----turns off PRL
2. GIH (growth hormone) inhibiting hormone ---turns off GIH

7

Name the 7 hormones that anterior pituitary secretes.

1. TSH (Thyroid-stimulating hormone)
2. ACTH (Adrenocorticotrophic hormone)
3. FSH (Follicle-stimulating hormone)
4. LH (Luteinising hormone)
5. GH (Growth hormone)
6. PRL (Prolactin)
7. MSH (Melanocyte-stimulating hormone)
* The first 4 hormones are tropic.

8

Name the 2 hormones that posterior pituitary secretes.

8. ADH (antidiuretic hormone), or vasopressin
9. Oxytocin

9

Thyroid Stimulating Hormone (TSH)

TSH stimulates the thyroid to produce thyroid hormone

10

Adrenocorticotropin hormone (ACTH)

ACTH stimulates the adrenal cortex to produce corticosteroids: aldosterone and cortisol

11

FSH (follicle stimulating hormone)

FSH stimulates follicle growth and ovarian estrogen production; stimulates sperm production and androgen-binding protein

12

LH (Luteinising hormone)

LH has a role in ovulation and the growth of the corpus luteum; stimulates androgen secretion by interstitial cells in testes

13

GH (Growth hormone)

GH stimulates growth of skeletal epiphyseal plates and body to synthesize protein

14

PRL (Prolactin)

PRL stimulates mammary glands in breast to make milk

15

melanocyte stimulating hormone (MSH)

MSH stimulates melanocytes; may increase mental alertness

16

Antidiuretic Hormone (ADH)

ADH (antidiuretic hormone AKA vasopressin) stimulates the kidneys to reclaim more water from the urine, raises blood pressure

17

Oxytocin

Oxytocin prompts contraction of smooth muscle in reproductive tracts, in females initiating labor and ejection of milk from breasts

18

posterior pituitary

Posterior pituitary does not produce any hormones it only releases hormones that are made in the hypothalamus. Oxytocin and ADH are stored in the posterior pituitary.

19

anterior pituitary

Cells in the anterior pituitary will signal to make another hormone and that hormone will be send to the blood supply.

20

peptide hormones

Cellular action mechanism
Hydrophilic (Lipophobic) – must bind to receptors on membrane’s ECF surface
Most work via cAMP messenger system
Cannot diffuse across cell membranes
Can move through blood and ECF without receptor

21

Thyroid hormone

Increases the basal metabolic rate.

Affects many target cells throughout the body; some effects are
Protein synthesis
Bone growth
Neuronal maturation
Cell differentiation

22

When calcium is too high you secrete

Calcitonin (thyroid)

23

When calcium levels is too low you secret

Parathyroid hormone

24

Aldosterone

Secreted by adrenal cortex in response to a decline in either blood volume or blood pressure

25

Cortisol

Helps the body deal with stressful situations within minutes. you don't want to make too much cortisol for a long period of time.
Ex:
Physical: trauma, surgery, exercise
Psychological: anxiety, depression, crowding
Physiological: fasting, hypoglycemia, fever, infection

26

What happens when you are stressed out?

Hypothalamus releases Corticotropin-Releasing Hormone, CRH binds to anterior pituitary makes ACTH to adrenal cortex. Adrenal cortex can make a negative feedback of cortisol but if you are so stressed out the negative feedback might not work.

27

responsible of making melatonin

the pineal gland

28

What are hormones?

Chemical messengers secreted by specialized cells.
Involved in
Growth
Development
Metabolism
Reproduction

29

Down-regulation vs. desensitization of hormones

Down regulation is slower as cell needs to remove receptors from membrane.
Desensitization is quicker as a binding agent can deactivate the receptor.

30

How do hormones get from point A to B?

***Travel in blood***

-May require water soluble (protein) transport mechanism if hormone is lipid soluble
-Hydrophilic hormones act by binding to receptor on target cells

31

The three types of hormones?

peptide/protein, steroid and amino acid base hormones

32

peptide hormones

Cellular action mechanism
-Hydrophilic (Lipophobic) – must bind to receptors on membrane’s ECF surface
-Most work via cAMP messenger system
-Cannot diffuse across cell membranes
-Can move through blood and ECF without receptor

33

Steroid hormones

-Hydrophobic (Lipophilic) – creates problems
-No storage: Production is on an “as needed” basis
-Cholesterol based
-Produced in the adrenal cortex, gonads and placenta
-Require protein transports in blood

34

Steroid Hormone regulation

-Negative feedback loop – increased transcription factors cause a decrease in production
-Phosphorylation – may stop transcription
-Ligand binding to transcription factors or cofactors that regulate the transcription factors

35

Amino Acid Hormones

Amino acid derived hormones may be derived
from tyrosine:
-T3 & T4
-Epinephrine & norepinephrine

Amino acid derived hormones may be derived from tryptophan
-Melatonin
-Serotonin*

36

Function of endocrine system

is made up of glands that produce and secrete hormones, chemical substances produced in the body that regulate the activity of cells or organs. These hormones regulate the body's growth, metabolism (the physical and chemical processes of the body), and sexual development and function.