HUBS1403 Lecture 20: Lecture 20- Hormone Secretions and Actions 1
8 Jun 2018
School
Department
Course
Professor
Hormone Secretions and Actions 1
Posterior Pituitary Gland
• Does not synthesise hormones
• Stores and releases from axon terminals 2 hormones produced by neurosecretory cells of the
hypothalamus:
o Oxytocin (OT)
o Anti-diuretic hormone (ADDH)
Posterior Pituitary Hormones
Hormones
Target Tissues
Control of Secretion
Principle Actions
Oxytocin
(OT)
Uterus
Mamary glands
Neurosensory cells of
hypothalamus secrete OT in
response to uterine distension and
stimulation of nipples
Stimulated contraction of
smooth muscle cells of
uterus during childbirth;
stimulate contraction of
myoepithelial cells in
mammary glands to
cause milk ejection
Antidiuretic
Hormone
(ADH)
Aka
vasopressin
Kidneys
Sweat Glands
Arterioles
Neurosensory cells of
hypothalamus secrete ADH in
response to elevated blood osmotic
pressure, dehydration, loss of
blood volume, pain, or stress;
inhibitors of ADH secretion include
low blood osmotic pressure, high
blood volume, ad alcohol
Conserves body water by
decreasing urine volume;
decreases water loss
through perspiration;
raises blood pressure by
constricting arterioles
Anterior Pituitary Gland
• Secretes 7 hormones produced by 5 different types of cells:
Hormone
Secreted by
Hypothalamic Releasing
Hormone (stimulates
secretion)
Hypothalamic Inhibiting
Hormone (supresses
secretion)
Human Growth
Hormone (HGH)
Aka somatotropin
Somatotrophs
Growth hormone-releasing
hormone (GHRH)
Aka somatocrinin
Growth hormone-
inhibiting hormone
(GHIH)
Aka somatostatin
Thyroid-stimulating
hormone (TSH)
Aka thyrotropin
Thyrotophs
Thyrotropin-releasing
hormone (TRH)
Growth hormone-
inhibiting hormone
(GHIH)
Follicle-stimulating
hormone (FSH)
Gonadotrophs
Gonadotropin-releasing
hormone (GnRH)
-
Luteinizing Hormone
(LH)
Gonadotrophs
Gonadotropin-releasing
hormone (GnRH)
-
Prolactin (PRL)
Lactotrophs
Prolactin-releasing
hormone (PRH)*
Prolactin-inhibiting
hormone (PIH) which is
dopamine
Document Summary
Posterior pituitary gland: does not synthesise hormones. Stores and releases from axon terminals 2 hormones produced by neurosecretory cells of the hypothalamus: oxytocin (ot, anti-diuretic hormone (addh) Neurosensory cells of hypothalamus secrete ot in response to uterine distension and stimulation of nipples. Neurosensory cells of hypothalamus secrete adh in response to elevated blood osmotic pressure, dehydration, loss of blood volume, pain, or stress; inhibitors of adh secretion include low blood osmotic pressure, high blood volume, ad alcohol. Stimulated contraction of smooth muscle cells of uterus during childbirth; stimulate contraction of myoepithelial cells in mammary glands to cause milk ejection. Conserves body water by decreasing urine volume; decreases water loss through perspiration; raises blood pressure by constricting arterioles. Secretes 7 hormones produced by 5 different types of cells: Dopamine hormone (crh) (*) thought to exist, but exact nature is uncertain: human growth hormone (hgh, most plentiful anterior pituitary hormone, released in bursts every few hours by somatotrophs.
