ANS Flashcards
Function of the ANS
The function of the ANS is to regulate visceral activities normally outside the real of consciousness and voluntary control
Can accelerate or decelerate systems
Sympathetic dominance
- Increased HR and SV = increased CO
- Increased resp rate and airway dilation
- Blood vessels are ONLY controlled through symp
Varicosity
area over the effector organ that contains neurotransmitters
Differences between sympathetic and parasympathetic
Parasympathetic:
Exit in the neck via cranial nerves or low in the trunk
Ganglia close to effector organ (longer pre ganglionic fiber)
ACh receptors on target organ
Sympathetic:
Exit from the torso
Ganglia great distance from effector organ
NE and E on effector organ
Receptors on post ganglionic fibres and effector organs
Both have ACh receptors on post ganglionic fiber
Para have AcH on effector organ
Symp have NE or E on effector organ via blood stream
Adrenal medulla
The adrenal medulla is a modified sympathetic ganglion that secrete hormones directly into the blood upon stimulation. It also produces adrenaline.
Receptor types in para vs symp
Cholonergic receptors on both symp (has adrenergic on effector organ) and para on post ganglionic fibres
What are cholinergic receptors
Respond to AcH release
Nicotinic
On all autonomic ganglia
Muscurinic
On parasympathetic effector cells
What are adrenergic receptors
On sypathetic effector cells and have varying degress of affinity for Na/A
Alpha 1 (NE) Alpha 2 (NE) Beta 1 (NE=E) Beta 2 (E)
Alpha 1 receptors
> NE
Excitatory effect smooth muscle
Arterioles
Alpha 2 receptors
> NE
Inhibitory smooth muscle
Digestive tract
Beta 1 receptors
NE=E
Excitatory effect
Heart
Beta 2 receptors
> E
Inhibitory effect on smooth muscle arterioles (SkM) and bronchioles