Endocrinology
,Hormone: Chemical substance produced
and secreted into blood stream by an
organ or tissue and has a specific effect
on a target tissue usually (but not always)
located at some distance from its site of
production
, Chemically hormone can be:
1) STEROIDS
◼ Produced by Adrenal gland( cortisol ,
aldosterone , androgens) ,Gonads
(Estrogen , Progesterone, Testosterone)
and Placenta (HCG)
◼ All are produced from Cholesterol
◼ Synthesized when needed No stores
◼ Lipid soluble
◼ Circulate bound to plasma proteins
◼ Long half-life (60-80 mins)
, 2) PROTEINS
◼ Peptides or Glycoproteins (FSH, LH, TSH,
HCG )
◼ Glycoproteins have alpha and beta
subunits
◼ Alpha chain of all is identical
◼ Functional and immunological specificity is
due to beta chain
◼ Peptides include Insulin , Glucagon, PTH,
GH and Prolactin
,Hormone: Chemical substance produced
and secreted into blood stream by an
organ or tissue and has a specific effect
on a target tissue usually (but not always)
located at some distance from its site of
production
, Chemically hormone can be:
1) STEROIDS
◼ Produced by Adrenal gland( cortisol ,
aldosterone , androgens) ,Gonads
(Estrogen , Progesterone, Testosterone)
and Placenta (HCG)
◼ All are produced from Cholesterol
◼ Synthesized when needed No stores
◼ Lipid soluble
◼ Circulate bound to plasma proteins
◼ Long half-life (60-80 mins)
, 2) PROTEINS
◼ Peptides or Glycoproteins (FSH, LH, TSH,
HCG )
◼ Glycoproteins have alpha and beta
subunits
◼ Alpha chain of all is identical
◼ Functional and immunological specificity is
due to beta chain
◼ Peptides include Insulin , Glucagon, PTH,
GH and Prolactin
