Transcript bio 342 human physiology

Wednesday, 21 September
Chapter 11 The Endocrine System
Chapter 6 Nervous System A and B
Two 1QQs returned on Piano
Lab this week: Analyzing a research paper + First Endocrine Case study.
Lab next week: Four more cases in endocrinology
1QQ # for 8:30
Write the number of the one question you choose to answer.
1) Suppose the portal vessel that connects the median eminence to the
adenohypophysis was completely occluded (blocked.) Which
hypothalamic hormone(s) could not reach their target cells?
a) ACTH b) CRH c) DA d) Prolactin
e) TRH
f) TSH g) FHS h) T3
i) GnRH j) ADH
OR
2A Name the hormone normally secreted by hepatocytes.
2B Name the hormone secreted by cells in the adenohypophysis that
stimulates the secretion of the “liver” hormone.
2C Suppose liver cells form a tumor that secretes the “liver” hormone in
an unregulated manner. Assuming cells in the adenohypophysis are
behaving normally, would the levels of the tropic hormone from the
anterior pituitary be normal, high, or low?
1QQ # for 9:30
Write the number of the one question you choose to answer.
1) Suppose the portal vessel that connects the median eminence to the
adenohypophysis was completely occluded (blocked.) Which
hypothalamic hormone(s) could not reach their target cells?
a) Oxytocin b) Prolactin c) DA d) CRH
e) TRH
f) TSH
g) FHS
h) T3 i) GnRH j) ADH
OR
2 Cells in the anterior pituitary gland that secrete TSH
a) have receptors for TRH in their cell membranes
b) can sense the levels of T3 and T4 in the plasma
c) will release more TSH as levels of TRH rise
d) Should release less TSH after a person has been treated with
radioactive iodine
e) Should release less TSH if a person is dosed with exogenous TH.
Tropic hormones control the function
S6
Trophic hormones promote survival and growth of targets
P P
P
P
A
P
Hypothalamo-hypophyseal portal system
P
P
S
P
P
P
A
Releasing Hormone
Release-inhibiting Hormone
P
S
Tropic hormones control the function
Trophic hormones promote survival and growth of targets
Short-loop Neg. Feed.
Long-loop negative feedback
Releasing Hormone
Release Inhibiting Hormone
S7
Vasopressin
Cytokines
from
immune cells
CRH from Hypothalamus
ACTH from Ant. Pit
⇧Cortisol
secretion from
Adrenal Cortex
S8
Physical trauma
Prolonged exposure to cold
Prolonged intense exercise
Infection
Sleep deprivation
Pain
Fright
Emotional distress
Basal levels of Cortisol
Required for normal sensitivity to EPI;
symptoms of excess cortisol are…..
Clinical example: treatment of chronic inflammation
(e.g. arthritis) with high doses of cortisol can lead to
Cushing’s Syndrome!
Mobilize fuel from muscle & adipose tissue
Suppress non-essential functions
(reproduction & growth)
Suppress inflammatory &
immune responses
Potentiates response to EPI (vascular
smooth muscle)
Cushing’s Syndrome
Excess Cortisol from
1) adrenal cortex tumor (primary) or
2) hypersecretion of ACTH from anterior pituitary (secondary)
Who Cares?
Vasopressin
Cytokines
from
immune cells
CRH from Hypothalamus
S8
Physical trauma
Prolonged exposure to cold
Prolonged intense exercise
Infection
Sleep deprivation
Pain
Fright
Emotional distress
ACTH from Ant. Pit
⇧Cortisol
secretion from
Adrenal Cortex
Mobilize fuel from muscle & adipose tissue
Suppress non-essential functions
(reproduction & growth)
Suppress inflammatory &
immune responses
Potentiates response to EPI (vascular
smooth muscle)
Age 16, 33, 52
No Relation!
S4
Disorder =Acromegaly
Type of endocrine disorder = ????
GHRH SS
GH
S5
• Excessive growth of
bones and soft tissues
of face and hands, and
feet.
• Hypersecretion of
Growth Hormone from
adenohypophysis or
ectopic tumor in adults
• Treatment?
• Somatostatin analogs?
• GH receptor blockers
• Transphenoidal
resection/ablation with
focal radiation
Compare to Pituitary Gigantism
S9
Applied Physiology: Menopause
Widmaier text p. 626-7
•
•
•
•
Onset ~ age 50
Irregular menstrual cycles
Breasts and genital organs gradually atrophy
Decrease in bone mass & strength
(osteoporosis)
(bone resorption > bone deposition)
• Hot flashes…sweating, etiology unknown
• Increased incidence of coronary artery disease
Menopause, continued.
• Caused by ovarian failure….loss of estrogen
• Estrogen has protective function for
cardiovascular system and sustains bone
• Diagnosis
– Test estrogen levels
– Test FSH levels….interpretation if high?
• Treatment
– Hormone replacement therapy
– Risk of HRT: increased incidence of breast
cancer & uterine endometrial cancer
– Advantages: alleviates symptoms, restores
cardiovascular protection, sustains bone density
S 10
S6
Neurons? Endocrine cells? Neuroendocrine cells?
Neurons and endocrine cells are very involved in homeostasis. To Chapter 6!