Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/74

Click to flip

74 Cards in this Set

  • Front
  • Back
What happens if there are small structural changes within steroids?
Large effects on activity.
Steroid hormones produced where?
-Adrenal cortex
-ovary
-placenta
-testes
-kidney
-local synthesis in skin,brai,bone.
Steroids synthetized from
Cholesterol
First rate limiting step in steroid synthesis?
-Cholesterol-->Pregnenolone
How many rings?
4
Estradiol compared to testosterone has
-OH group on A ring
What is the common intermediate in the pathway for cortisol and sex hormones prod. ?
17-OH progesterone
Type of steroid synthetized depends on
Enzymes present within cell.
How is steroid hormone synthesis acheived?
-Cholesterol uptake and transfer within cell(by Star)
-Conversion of cholesterol to pregnenolone
5 types of steroids?
1) Glucocorticoids
2) Mineralocorticoids
3) Androgens
4) Estrogens
5) Progestagens
What are the 3 types of glucocorticoids terms used?
-cortisone
-cortisol
-hydrocortisone
Cortisone is
metabolite of cortisol and biologically inactive.
Hydrocortisone is
drug for cortisol
Cortisol is
made by adrenal gland.
Cortisol is
stress hormone
Actions of cortisol:
-stimulate glc production in liver
-inhibit glc uptake in muscle
-stimulate protein and fat breakdown
-anti-inflammatory
Glucorticoids maintain
BP
Acute effect of GCS is
stress response.
Long term effects of GCS are
Opposite to the short term effects.
GCS regulated by
ACTH released from pituitary.
How is cortisol released from adrenal cortex?
1) Stress acts on hypothalamus which releases CRF
2)CRF acts on pituitary to release ACTH
3)ACTH acts on adrenals to release cortisol.
Red striae is due
to thinning of subcutaneous tissue.
When do you have increased pigmentation of fingers?
-In Addisons: increased ACTH which increases activity of melanocytes.
Cushings
-can be due to ACTH producing tumour of pituitary
-increased adipose tissue
-lemon on stick
-muscle wasting
Mineralocorticoids produced in
Adrenal cortex
Actions of Aldosterone :
-Regulation of salt and water balance via Na+ retention
-regulation of serum K+ via K+ loss.
Mineralocorticoids regulated by:
-Renin/angiotensin
-K+
Androgens?
-Testosterone
-Dihydrotestosterone(DHT)
-DHEA
Precursor of Testosterone and DHT?
DHEA
Androgens produced where?
-Testis
-Ovary
-Adrenal
Androgenic effects:-
-Control sexual differentiation
-Regulate function in male reproduction
Anabolic effects:
Promote growth of bone,muscle,prostate.
Main androgen?
Testosterone
Functions of testosterone in men?
-Masculinising(androgenic)
-Growth promoting(anabolic)
What regulates reproduction in males?
Testosterone
When is the first burst of testosterone occur?
-In utero-dev. of male genitalia
Testosterone expressed at
Puberty also.
At birth,neonates have same levels of testosterone as adult males.
True
In women,where is aromatase found?
Everywhere.
Oestradiol is synthetized from
Testosterone
In ovaries what convert testosterone to oestradiol?
Aromatase(nt present in testis)
What regulates androgens?
LH released from pituitary.
Testosterone inhibits its own synthesis if its conc. increases.
True
What are the oestrogens?
-Estradiol,Estriol,Estrone
Where are estrogens produced?
-Ovary and placenta
Functions of estrogens in women:
-Regulate sexual development
-Regulate reproductive dev.
What happens with congenital adrenal hyperplasia/
Precocious puberty.
Main estrogen?
Estradiol(main female hormone)
Functions of estradiol?
-feminising function
-effects on body shape,breast development,reproduction.
When is estrogenic puberty expressed?
Initially in utero and then at puberty.
How is estrogens regulated?
LH and FSH from pituitary.
Oestrogens have both +ve and -ve feedbacks on hypothalamus and pituitary.
True
What acts on pituitary to release LH and FSH?
GnRH ( LHRH)
Menopause?
-Period stops
-Fractures
-Mood changes
-Change in CV risk
Excess cotisol causes?
Cushings sundrome
Cortisol deficiency?
Addisons disease
Aldosterone excess?
Conn's syndrome
Aldosterone deficiency?
-Hypotension
-Hyperkalaemia(potentially fatal)
Excess testtosterone?
-Precocious puberty in males/females
Testosterone deficiency?
-XY female
-Delayed puberty
-Hypogonadism
Excess estradiol?
Precocious puberty
Estradiol deficiency?
-delayed puberty
-hypogonadism
-menopause
Steroids circulate in blood in contact with
Binding proteins.
Binding proteins for testsoterone and oestradiol?
-Sex hormone binding globulin(SHBG) (specific,high affinity)
Binding protein for cortisol?
-Cortisol binding globulin(CBG)(specific, high affinity)
Non-specific and low affinity binding proteins for steroids?
Albumin
Are steroids stored in cells?
No,its not stored!!-synthetized when required.
Mechanism of steroid action:-
-Cross cell mb being lipi soluble
-Enter all cells
-bind to specific receptors.
-receptors dimerise & bind to co-activator proteins.
-receptor complex binds to specific DNA sequences
-Regulate gene expression
-Steroid action is via protein synthesis.
On binding of steroid to steroid receptor,there is dissociation of
Heat shock proteins
Receptor complex bind to
Hormone response elements(HRE) on DNA.
Steroid receptors?
-Hormone dependent transcription
-Steroid action occurs via regulation of responsive genes
-Tissue-specific effects occur via diff. genes.(act via peptide-like mb receptor:non genomic effects)
Steroids' clinical uses?
-Replacement if inadequate production
-Contraception(estradiol,progesterone,testosterone)
-Anti-inflammatory(cortisol)
-Body building(testosterone)
Steroids are
Small lipid molecules.
Steroid levels in blood are regulated by
Rate of steroid synthesis.