Lecture 20 Flashcards

1
Q

Critical regulatory center of the nervous system is the _______ and is the major _______ between the nervous system and the endocrine system

Synthesizes a variety of different “R” (Releasing) and Inhibiting hormones:

TRH, GnRH, GHRH, CRH, and also ADH, Oxytocin, Prolactin inhibiting hormone (dopamine), Growth hormone inhibitory hormone (somatostatin)

A

hypothalamus
link

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pituitary gland secretes a number of different hormones

Together, the Hypothalamus and the Pituitary gland regulate __________

A

growth, development, metabolism, and homeostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Hypothalamus controls the secretion of the _______ pituitary

Does this by secretion of hormones called ______ and _______ hormones

These hormones are transported to the anterior pituitary through minute blood vessels called _______

A

anterior

hypothalamic releasing
hypothalamic inhibitory

hypothalamic-hypophysial portal vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Hypothalamic hormones reach the anterior pituitary gland through the ________ system

Transports blood from a ______ capillary network to capillaries into a _____ capillary network (in the anterior pituitary) without passing through the _____

Hormones will then pass into the anterior ________and out into the general circulation to travel to target tissues

A

hypophyseal portal

primary
second
heart

hypophyseal veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

____________ (branches of internal carotid arteries) bring blood to the hypothalamus.

At the _________ these arteries divide into a ___________ of the hypophyseal portal system

This plexus drains blood into the ________ which pass down the infundibulum

Within the pituitary the portal veins divide into a _________ of the hypophyseal portal system

A

Superior hypophyseal arteries

infundibulum
primary capillary plexus

hypophyseal portal veins

secondary plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Pea-shaped structure about ½ inch in diameter

A

Pituitary Gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

pituitary gland lies within the ________ of the ________ of the ______ bone

Attached to the hypothalamus by a stalk called the ________

Anterior/posterior two different cell types

A

hypophyseal fossa
sella turcica
sphenoid

infundibulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

2 structurally and functionally different areas of the pituitary or hypophysis

A

Anterior Pituitary (adenohypophysis)
Posterior Pituitary (neurohypophysis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Anterior Pituitary (adenohypophysis) accounts for ____% of the total weight

contains _____ different types of hormone-secreting cells

A

75%

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Posterior Pituitary (neurohypophysis) contains ____ and ________ of more than 10,000 different neurons

cell bodies of these neurons are located in the _______ and _______ of the hypothalamus

secretes ____ major hormones of the endocrine system

A

axons
axon terminals

supraoptic
paraventricular nuclei

two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Regulates a wide range of physiologic functions from growth to reproduction

A

anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

40% of cell mass is __________

secrete ______________

hGH stimulates a variety of tissues to secrete ___________, which stimulate body growth and regulates metabolism

A

Somatotrophs

human growth hormone (hGH or somatotropin)

insulin-like growth factors (IGFs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

secrete thyroid-stimulating hormone (TSH or thyrotropin)
stimulates secretion of thyroid gland

A

Thyrotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

secrete both follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

  • both FSH and LH control growth of the ovaries and testes, as well as their hormonal and reproductive activities
A

Gonadotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

secrete prolactin (PL) which stimulates milk production in mammary glands

A

Lactotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

20% of cell mass is ___________

A

Corticotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Corticotrophs secrete _________ and _________

A

adrenocorticotropic hormone (ACTH) or corticotropin
melanocyte-stimulating hormone (MSH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

ACTH stimulates the _______ to secrete _______

A

adrenal cortex
glucocorticoids

19
Q

MSH stimulates _______, increasing ________

A

melanocytes
skin pigmentation

20
Q

human growth hormone is a single chain of ____ amino acids
- Stimulates body growth
- Both cell size and number of cells
- Stimulates secretion of ____________
- Proteins produced primarily in the _____
- Require growth hormone to carry out function of increasing bone growth

A

191
Insulin-like growth factor -1
liver

21
Q

Human growth hormone
- Inhibits ______ action on carbohydrate and lipid metabolism
- Promotes _______ synthesis
- Facilitates AA transport across the cell and increases RNA translation
- Limits breakdown of _____
- Stimulates _____, mobilization and utilization of fatty acids as energy

A

insulin
protein
proteins
lipolysis

22
Q

human growth hormone
- Conservation of glucose
- _____ glucose uptake skeletal muscle and fat
- _______ glucose production in liver
- ______ insulin secretion by the pancreas
- “_______”: looks like Type II diabetes when GH is in excess. (unknown cause- likely GH’s associated increase in fatty acids)
- GH in absence of carbohydrates or insulin? _______

A

Decreases
Increases
Increases
diabetogenic
No growth

23
Q

human growth hormone
- Integral in cartilage formation and bone growth
- Deposition of new cartilage _______ (which converts to bone in growing individuals)
- Promotes ______ activity manufacturing the boney matrix

A

epiphyseal region
osteoblast (build bone)

24
Q

stimulate or inhibit GRWOTH HORMONE
- low blood sugar hypoglycemia will _____

A

stimulate GH

25
Q

Hypothalamic Stimulation of the Posterior Pituitary

Secretion from the posterior pituitary is controlled by nerve signals that originate in the hypothalamus and terminate in the posterior pituitary

Hormones are secreted by specialized cells called _________ located in the hypothalamus

Hypothalamus produces ____ and _____, packaged into secretory vesicles that are transported via carrier proteins called ______ down to the nerve endings in the posterior pituitary. This process takes several days.

A

magnocellular neurons

ADH
oxytocin
neurophysins

26
Q

in the posterior pituitary the hormones are stored until nerve impulses trigger ______ and release of the hormones

hormones enter the posterior pituitary circulation until they reach the general circulation where they travel to their target tissues

A

exoctyosis

27
Q

Structure of Posterior Pituitary:

Consists of axon terminals of________ cells which form the ____________ tract.

Blood is supplied to the posterior pituitary by the _______ (branches of internal carotid arteries), which drain into the capillary network of the _______ where OT and ADH are secreted
From this plexus hormones pass into the ________ and into the general circulation where they travel to their target tissues.

A

hypothalamic neurosecretory
hypothalamohypophyseal

inferior hypophyseal arteries
infundibular process

posterior hypophyseal veins

28
Q

peptide containing 9 AA synthesized primarily by the ___________

stimulates contraction of smooth muscle of the uterus during childbirth

stimulates contraction of myoepithelial cells in mammary glands for milk ejection (let down).

what hormone is this?

A

paraventricular nucleus

oxytocin

29
Q

peptide containing 9 AA synthesized primarily by the ____________

decreases urine volume and sweat gland activity, thus conserving body water

raises BP by constricting arterioles (vasopressin)

A

supraoptic nucleus

Antidiuretic hormone
(ADH; vasopressin)

30
Q

Regulation of ADH Production

__________ within hypothalamus
Sensitive to osmotic pressure of serum
_______ in size as osmolarity increases
In the kidney, water will move toward the region of higher solute concentration, i.e. from the ______ solution to the ______ solution, eventually producing an isotonic solution
Movement of water through the membrane requires ________ (in the kidney- collecting tubules)
______ acts on the cell to increase availability of these proteins

A

Osmoreceptors
Shrink
hypotonic
hypertonic
aquaporins
ADH

31
Q

Low Blood Volume and ADH Secretion

Trigger: ____________

Sensed by decrease in _________________

In turn sends signals to brain to release ____

A

Intravascular volume depletion 20%

atrial stretch receptors, carotid, aortic baroreceptors

ADH

32
Q

The Hypothalamus’ other functions include the ______ System

A

Limbic

33
Q

Hypothalamus represents less than____% of the brain mass, but controls most of the _____ system

Also: senses blood levels of various hormones, aids in arterial pressure control and heart rate, stimulates hunger, thirst and the GI tract, initiates satiety after eating, controls bladder contraction and urine production, pupillary dilation, and regulates body temperature. It regulates uterine contractions and stimulates milk secretion in the breasts.

Behaviorally, the hypothalamus stimulates the general activity level, and if overstimulated can lead to __________.

A

1%
limbic
rage and fighting

34
Q

Frequently the behavioral aspects are linked to physiologic effects due to this hypothalamic overlap

Satiety is diminished drive to eat, and a sense of tranquility after eating

____ and the reaction to __________ are elicited in the hypothalamus

______ is primarily a hypothalamic-mediated response

A

Fear
punishment

Sexual drive

35
Q

These areas of the limbic system provoke _______, as well as causing the sensation of needing to escape.

These centers are in the _________

less potent areas are in the ______________.

A

fear and shame

mesencephalon
periventricular hypothalamus
thalamus

amygdala and hippocampus

36
Q

limbic system is our _____ and _____ center

A

reward and punishment

37
Q

punishment stimulation and fear can overcome the ________ centers completely, with the result that punishment and fear (anxiety?) can take precedence in the mind over pleasure and reward.

A

reward and pleasure

38
Q

Reward: Located primarily in the _____ and the _______, these areas were found by electrically stimulating areas of the brain in primates.

Primates deprived of food will press a lever delivering stimulation to reward centers in the brain rather than receive food.

Less potent reward centers exist in the _________________

Stronger stimuli to the same areas of the brain that are reward centers (lateral hypothalamus) can cause______ (we don’t know why).

A

forebrain
lateral hypothalamus

septum, amygdala, thalamus, and basal ganglia

rage

39
Q

Rage comes from the _________. Despite association with reward area of _____________, rage primarily involves the __________ centers

A

limbic system
lateral hypothalamus
punishment

40
Q

Held in check by inhibitory signals from the ________, the hippocampus, and the anterior limbic cortex.

Consistent lower-level overstimulus of the reward centers of the brain result in ______________.

A

ventromedial hypothalamus
placidity and tameness

41
Q

The hypothalamic pituitary axis is composed of the ______________________

A

hypothalamus, infundibular stalk, posterior and anterior pituitary

42
Q

Arginine vasopressin (ADH) and oxytocin are synthesized in the ______________ whose axons terminate in the __________

A

hypothalamic neurons
posterior pituitary

43
Q

Hypothalamic growth hormone releasing hormone increases growth hormone secretion from ____________, which in turn stimulate the release of insulin like growth factor 1 from liver

Aging, deep sleep, stress, exercise and hypoglycemia are a few examples known to regulate GH secretion
GH assists in multiple physiologic processes within the body

A

somatotrophs