13. assification of Hormone
Peptides
s Synthesis as Pro hormones
requiring further processing
(eg.Clevage) to activate
Stored in vesicle
(regulatory system)
Most are polar and water
soluble,can travel freely in the
soluble,can travel freely in the
blood
Bind receptor on cell
membrane and transduce
signal via the use of second
messanger system
Often fast oneset transient
change in protein activity
through gene expression
changes can occurs
s Insulin,Gkucagon,Prolactin,AC
TH,gastrin Parathyroid
hormone
Steroids Amino acid deriva
Synthesis in a series of
reaction from cholesterol
Synthesis from the am
tyrosine
Released immediately
(constitutative Secretion )
Stored before release
(Storage mechanism
Generally non polar and require
carrier protein to travel in blood
Some are polar
(adrenaline),other mu
carrier protein to travel in blood (adrenaline),other mu
protein – bound
Bind to intracellular receptor to
change gene expression
directly
Adrenaline act on me
receptor,while thyroid
act directly on nuclea
Alteration in gene expression
slower onset but longer
duration than peptide hormone
Adrenaline Function l
peptides,thyroid horm
function in a similar m
steroids
Cortisol,Aldesterone,Progester
one,testesterone
Adrenaline,thyroxin,tr
iodothyronine
