Nervous/Endocrine Flashcards
Sympathetic nerve fibres innervate what vessels?
All vessels except capillaries and precapillary sphincters which follow local control
Why are blood vessels to the skin vasoconstricted during sympathetic response?
To minimise bleeding if injury occurs during stress or exercise
Give three examples of neurocrine communication
Anterior pituitary
Posterior pituitary
Adrenal medulla
Name some of the major endocrine glands/organs
Hypothalamus Pituitary gland Thyroid gland Thymus Pancreas Adrenal glands Gonads
What’s the role of the thymus
In the maturation of bone marrow derived stem cells into immunocompetent T cells (thymic cell education). It produces thymosin, a hormone that promotes T cell maturation
What does the hypothalamus produce?
ADH and oxytocin (travel to of pituitary)
6 hormones that travel via the hypothalamus-hypophyseal portal system to anterior pituitary (4 stimulatory and 2 inhibitory)
What’s the role of thyrotropin?
Broadly speaking controls metabolic rate
Produced by the thyroid gland
What’s the link between the hypothalamus, pituitary gland and thyroid?
Hypothalamus releases thyroid releasing hormone (TRH) travels through the hypothalamo-hypotheseal portal system to the anterior pituitary where cells release thyrotropin secreting hormone (TSH) into the blood stream. Acts on thyroid gland - release of T3 and T4.
How is stress commonly defined?
A state of real or perceived threat to homeostasis
Give some examples of the behavioural effects of the stress response
Increased awareness
Improved cognition
Euphoria
Enhances analgesia
Give some examples of the physiological adaptation of the stress response
Increased heart rate
Increased respiratory rate
Intermediate metabolism
Inhibition of digestion, growth, reproduction, immunity
What are the adrenal cortical hormones?
Glucocorticoids (cortisol)
Mineralocorticoids (aldosterone)
What is the pathway of neutrons in the autonomic nervous system?
ANS – two neurons from CNS to effectors
• presynaptic neuron whose cell body is in CNS
• postsynaptic neuron with cell body in peripheral ganglion
What cells make up the medulla of the adrenal glands?
Parenchyma of large epithelioid cells called chromaffin cells (modified neutrons). Act in secretion of noradrenaline and adrenaline.
myelinated, presynaptic sympathetic nerve fibers pass directly to
chromaffin cells
What are the hormones of the posterior pituitary and where are they secreted?
oxytocin and ADH (produced by hypothalamus)
travel down the neuronal axons and are secreted into adjacent capillaries
