HC 1 + 2 22-04-2014
Homeostatic fixed setpoints;
- pH
- Temperature
- Glucose levels in blood
- Ca2+ levels in blood
Variable setpoints;
- Ontogenisis (growth)
- Daily or seasonal cycles
o Day or night
o Ovarian cycles
o Migration, hibernation
To maintain homeostasis the endocrine system and nervous system work together.
Hormones regulate:
- Internal environment
- Growth and development
- Metabolism
- Reproduction
Hormone; produced by a gland not connected to the outside world. It is secreted into the
blood and performs physiologic or morphogenetic functions in the body, usually distant
from the site of production.
Endo: within
Krinein: to secrete
Logos: the study of
Endocrine glands:
- Pineal gland
melatonine
- Hypothalamus
releasing/inhibiting hormones
- Pituitary gland
o Frontal lobe
TSH, GH, ACTH, LH, FSH, PRL
o Intermediate lobe
MSH
o Neural lobe
ADH, oxytocin
- Thyroid gland
thyroid hormone, calcitocin
- Parathyroids
PTH
- Adrenal glands
o Cortex
aldosterone, cortisol, androgens
o Medulla
Adrenalin = epinephrine
- Pancreas
Insuline, Glucagon ….
- Ovaries/Testes
Reproductive hormones
,Endocrine cells and tissues
- Heart
Atrial natriuretic peptide
- Liver
angiotensinogen, insulin-like growth factor
- Stomach
Gasrtin
- Intestine
CCK, secretin, GLP-1, GIP
- Kidney
Erythropoietin, calciferol
- Skin
vitamin D3
- Adipose tissue
leptin, adiponectin
- Placenta
estrogen, progesterone, chorionic
gonadotropin, somatomammotropin.
- Several tissues
steroid production
Positive feedback example by hormones (picture):
- Does not lead to homeostasis
- Requires external interference to prevent
resonance catastrophe.
Membrane receptors;
- Lipophobic signal molecules mainly, also
some steroids.
- Vitamine A derivatives, some sex steroids,
peptides or catecholamines.
- G protein coupled
alfa-subunit binds to adenylate cyclase
converts ATP into cAMP activates PKA.
- Tyrosine kinase
o Steroids
Hormone binds receptor Chaperone released complex enters nucleus,
binds DNA transcription is activated.
o Thyroids
inactive hormone receptor already bound to DNA activated after binding
of thyroid hormone.
Intracellular receptors;
- Lipophilic signal molecules, diffuse through the cell membrane and bind to
cytosolic or nuclear receptors.
- Steroid hormones, thyroid hormones and calciferol (vitamine D derivative).
, HC 3 + 4
Hypothalamus:
- Derived from the bottem part of the diencephalon and upper part of stomodeum.
Rathke’s pouch is formed by a pouch from the roof of the mouth and a pouch
growing downwards from the brain, they grow together forms pituitary gland.
They are connected to each other by the pars tuberalis.
- Thirst, hunger, feelings (moods), temperature are measured and controlled here.
- Interface between neural system and endocrine system is formed by the neural-
endocrine neurons. Look just like neurons, only their axon ends on bloodvessels.
Two types:
o They make two different neural-hypothalamal hormones, axons run down
into the neural hypophysis where they contact capillairy bloodvessels.
Depending on the contents of the blood, they release the hormones.
Neurohypophysis is a neurohemo organ.
o Neuro endocrine neurons that produce releasing hormones or inhibiting
hormones responsible for regulating releasing hormones in the
adenohypophysis. These neurons end on capillary system where they
release their hormones.
Hypophysis / pituitary gland
- Pars distalis = adenohypophysis = posterior pituitary
Has six different celltypes to produce the 7 different hormones (LH and FSH are
produced by the same cells; gonadotropic cells).
- Pars nervosa = neurohypophysis = anterior pituitary
consists of mainly bloodvessels, axons and synapses filled with several types of
hormones from the hypothalamus.
- Pars intermedia in between
Hormone families of adenohypophysis
- POMC-derivatives (pro opio melano cortine)
o Derived from 1 gene, different splicing.
Expressed in the adenohypophysis ACTH production,
o ACTH has two byproducts: lipotropin, endofrin
o Expressed in pars intermedia MSH (melanocite stimulating hormone) is
produced, cleaved from ACTH.
- Glycoproteins
o LH, FSH and TSH
o α-unit is identical
o β-unit determines the biological specificity
- Somatomammotropins
o GH for postnatal growth
o PRL for milkproduction is mammals (behavior determined in non
mammals).
Hormone families of neurohypophysis
- Stores the hormones, they are made in the hypothalamus.
- Oxytocin
- Vasopressin
Homeostatic fixed setpoints;
- pH
- Temperature
- Glucose levels in blood
- Ca2+ levels in blood
Variable setpoints;
- Ontogenisis (growth)
- Daily or seasonal cycles
o Day or night
o Ovarian cycles
o Migration, hibernation
To maintain homeostasis the endocrine system and nervous system work together.
Hormones regulate:
- Internal environment
- Growth and development
- Metabolism
- Reproduction
Hormone; produced by a gland not connected to the outside world. It is secreted into the
blood and performs physiologic or morphogenetic functions in the body, usually distant
from the site of production.
Endo: within
Krinein: to secrete
Logos: the study of
Endocrine glands:
- Pineal gland
melatonine
- Hypothalamus
releasing/inhibiting hormones
- Pituitary gland
o Frontal lobe
TSH, GH, ACTH, LH, FSH, PRL
o Intermediate lobe
MSH
o Neural lobe
ADH, oxytocin
- Thyroid gland
thyroid hormone, calcitocin
- Parathyroids
PTH
- Adrenal glands
o Cortex
aldosterone, cortisol, androgens
o Medulla
Adrenalin = epinephrine
- Pancreas
Insuline, Glucagon ….
- Ovaries/Testes
Reproductive hormones
,Endocrine cells and tissues
- Heart
Atrial natriuretic peptide
- Liver
angiotensinogen, insulin-like growth factor
- Stomach
Gasrtin
- Intestine
CCK, secretin, GLP-1, GIP
- Kidney
Erythropoietin, calciferol
- Skin
vitamin D3
- Adipose tissue
leptin, adiponectin
- Placenta
estrogen, progesterone, chorionic
gonadotropin, somatomammotropin.
- Several tissues
steroid production
Positive feedback example by hormones (picture):
- Does not lead to homeostasis
- Requires external interference to prevent
resonance catastrophe.
Membrane receptors;
- Lipophobic signal molecules mainly, also
some steroids.
- Vitamine A derivatives, some sex steroids,
peptides or catecholamines.
- G protein coupled
alfa-subunit binds to adenylate cyclase
converts ATP into cAMP activates PKA.
- Tyrosine kinase
o Steroids
Hormone binds receptor Chaperone released complex enters nucleus,
binds DNA transcription is activated.
o Thyroids
inactive hormone receptor already bound to DNA activated after binding
of thyroid hormone.
Intracellular receptors;
- Lipophilic signal molecules, diffuse through the cell membrane and bind to
cytosolic or nuclear receptors.
- Steroid hormones, thyroid hormones and calciferol (vitamine D derivative).
, HC 3 + 4
Hypothalamus:
- Derived from the bottem part of the diencephalon and upper part of stomodeum.
Rathke’s pouch is formed by a pouch from the roof of the mouth and a pouch
growing downwards from the brain, they grow together forms pituitary gland.
They are connected to each other by the pars tuberalis.
- Thirst, hunger, feelings (moods), temperature are measured and controlled here.
- Interface between neural system and endocrine system is formed by the neural-
endocrine neurons. Look just like neurons, only their axon ends on bloodvessels.
Two types:
o They make two different neural-hypothalamal hormones, axons run down
into the neural hypophysis where they contact capillairy bloodvessels.
Depending on the contents of the blood, they release the hormones.
Neurohypophysis is a neurohemo organ.
o Neuro endocrine neurons that produce releasing hormones or inhibiting
hormones responsible for regulating releasing hormones in the
adenohypophysis. These neurons end on capillary system where they
release their hormones.
Hypophysis / pituitary gland
- Pars distalis = adenohypophysis = posterior pituitary
Has six different celltypes to produce the 7 different hormones (LH and FSH are
produced by the same cells; gonadotropic cells).
- Pars nervosa = neurohypophysis = anterior pituitary
consists of mainly bloodvessels, axons and synapses filled with several types of
hormones from the hypothalamus.
- Pars intermedia in between
Hormone families of adenohypophysis
- POMC-derivatives (pro opio melano cortine)
o Derived from 1 gene, different splicing.
Expressed in the adenohypophysis ACTH production,
o ACTH has two byproducts: lipotropin, endofrin
o Expressed in pars intermedia MSH (melanocite stimulating hormone) is
produced, cleaved from ACTH.
- Glycoproteins
o LH, FSH and TSH
o α-unit is identical
o β-unit determines the biological specificity
- Somatomammotropins
o GH for postnatal growth
o PRL for milkproduction is mammals (behavior determined in non
mammals).
Hormone families of neurohypophysis
- Stores the hormones, they are made in the hypothalamus.
- Oxytocin
- Vasopressin
