A walk through the brain - week 4 - Neurons Flashcards
How do neurotransmitters transmit through the synapse?
How do hormones differ from neurons?
Hormones differ from neurons in that they:
* Slower - over minutes to weeks
* Receive feedback from the region they contact rather than being ‘one-way’ communication;
* Are secreted in small pulses rather than a single burst;
* Vary in their levels according to the time of day (‘circadian rhythm’);
* Have different effects on different organs instead of the same effect of stimulating the
dendrites of another neuron.
What are neuroendocrine cells?
‘Neuroendocrine’ cells= hybrid of a neuron and an endocrine cell, so that they receive
neural signals but secrete hormones.
How many types of hormone categories are there?
3
What are the 3 group classifications of hormones?
Can be classified into 3 types
according to their chemical
structure (protein, amine,
steroid)
What is the biochemical process a steroid hormone has on a cell?
- Steroid hormone diffuses through cellular membrane
- The hormone binds to an intracellular receptor, in the cytoplasm or nucleus
- A hormone receptor complex forms
- The complex interacts with DNA in the nucleus, altering gene expression and cell function
What are 2 key biochemical functions steroid hormones have on a cell?
Change the cell’s DNA to
* Promote the cell’s differentiation and
development.
- Modulate the rate of function of a cell.
What are the hormone changes the DNA to produce
messenger RNA (mRNA)?
- mRNA sends ‘messages’ to produce new
proteins, thus changing behaviour.
What 8 hormones does the hypothalamus make?
- thyrotropin releasing hormone
- Dopamine
- Growth hormone releasing hormone
- Somatostatin
- Gonadotropin releasing hormone
- Corticotropin releasing hormone
- Oxytocin
- Vasopressin
What hormone does the pineal gland produce?
Melatonin
What 2 hormones does the thyroid gland produce?
- Thyroxine (T4)
- Triiodothyronine
What 6 hormones does the anterior pituitary gland produce?
- Growth hormone
- Thyroid stimulating hormone
- Adrenocorticotropic hormone
- Follicle stimulating hormone
- Lutienizing hormone
- Prolactin
What 3 hormones does the posterior pituitary gland produce?
- Vasopressin
- Oxytocin
- Anti-diuretic hormone
Name one glucocorticosteroid hormone?
Cortisol
What is the physiological steps in releasing cortisol?
What does the Paraventricular Nucleus of the Hypothalamus do?
Receives stimulation from
neurons and from hormones in
the bloodstream
What does the pituitary gland do?
- Receives stimulation from the hypothalamus.
- Each lobe produces
hormones for target cells
What area of the brain stimulates the paraventricular nucleus of the hypothalamus?
The amygdala
- Major source of emotional response
- Starts the corticotropin release of cortisol
What area of the brain inhibits the paraventricular nucleus of the hypothalamus?
The hippocampus
Checks CRH levels in blood and
provides FB to PVN to decrease CRH.
- Receives information from PFC to
adjust level of CRH-secretion.
What does Cortisol do for everyday homeostasis
- Stimulates the liver to synthesise glucose
- Controls Calcium levels
- Affects mood, appetite, sleep, memory, vision
- Affects skin & connective tissue, breast, lung and cardiovascular systems.
Cortisol: In stress responses
- Increases HR and BP (more O2 for muscle activity)
- Metabolises stored fats & amino acids to make glucose & protein
- Decreases cell usage of glucose (=more for muscles)
- Kills pathogens via lysosome phagocytosis
- Suppresses prolonged inflammation in 17 ways.,
Read C&B, pp. 435 to 444 about Stress Disorders
