Unformatted text preview: g hormones Anterior pituitary
growth factors hormones cortisol Key Points:
1. Hormones released from the Anterior Pituitary are produced IN the Anterior
P ituitary Glands.
H ORMONE: TSH: the endocrine cells that produce TSH sit here.
2. Hormones released from the Posterior Pituitary ARE NOT produced in the
Posterior Pituitary. They are produced by neurons sitting in the Hypothalamus -->
Project down to the Posterior Pituitary --> Released from here
HORMONES: ADH and Oxytocin estrogens,
testosterone, etc -You don't need to know where the cells sit
-You need to know that the hormones are produced outside the Posterior Pituitary -->
Neurons travel down --> Release in the Posterior --> Released into the vasculature to
c ause their effects "This is an important set of concepts here"
-Hormones released by hypothalamus --> Directly stimulate a Target Cell in the Anterior Pituitary 2 Inhibitory Hypothalamic Hormones:
SOMATOSTATIN AND DOPAMINE Growth Hormone Prolactin inhibits
inhibits HYPOTHALAMUS STIMULATES: MADE IN ANTERIOR PITUITARY: END TARGET: "FLAT PEG"
SRIF --> INHIBITS GH Release by Ant. P
Dopamine --> INHIBITS Prolactin Release by Lactotropes
TRH --> Stimulates TRH release by Thyrotrope
GNRH --> Stimulates Release of GH Release in Ant. P
CRH --> Stimulates Corticotrope to Release ACTH FSH - Produced by: Gonadotropes
LH - Produced by: Gonadotropes
ACTH - Produced by: Corticotrope
TSH - Produced by: Thyrotrope
PROLACTIN - Produced by: Lactotrope
ENDORPHINS (dont worry)
GH- Produced by: Somatotrope FSH/LH - Gonads
ACTH - Adrenal Gland
TSH - THYROID, Muscle GH - LIVER Hypothalamic Release Via Thyotropes in Ant Pit. TSH Stimulates Thyroid Gland "I will not ask you a question about the
f unction of the end hormone. Like T3 and
T4, I won't ask you anything about that" Through what mechanisms do the stimuli act?
• Act through intracellular pathways to:
change the membrane potential
increase free cytosolic Ca2+
change enzymatic activity "I'm not going tos ask you simple off all the changes
i n the cell, that' a lot of
increase the transport of hormone
substrates into the cell
alter transcription of genes coding for
hormones or for enzymes needed for
promote survival and in some cases growth
of the endocrine cell Review question #1
Sulfonylurea blocks KATP channels, what
effect would this have?
a) Keeps voltage-gated Ca2+ channels closed
b) Enhances insulin secretion
c) Causes the cell to hyperpolarize
d) Directly reduces the levels of ATP in the cell
-Drug blocks the KATP channel --> Keeps K++ inside the cell --> K++ remains inside the cell and is
a ble to further depolarize the cell --> More Ca++ influx -> MORE INSULIN RELEASE! -There is free...
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- Summer '12
- Endocrine System, Anterior pituitary