Neurophysiology and Renal Review Flashcards
Define: Transduction: Transmission: Perception: Interpretation: Modulation:
Transduction: process whereby energy and forces acting on the body are converted into nerve impulses @nerve endings
Transmission: process whereby information is carried from receptor to the brain
Perception: process of experiencing a particular stimulus
Interpretation: process of assigning a specific meaning to a stimulus
Modulation: process in which the sensation is dampened or modified
Myelin comes from what cells in the PNS? CNS?
Schwann cells
oligodendrocytes
In the resting state of a neuron is there more K+ inside or outside of the cell?
Inside
Describe the action potential
Na+ channels open to allow Na+ inside to depolarize membrane when peak is reached Na+ channels close, K+ channels open and after hyperpolarization ion channels return to resting state
Resting Membrane polarity in a neuron
-90 mV
Absolute refractory period
When membrane will not respond to further stimulus during depolarization
Relative refractory period
When membrane repolarizes it is difficult to depolarize but can with a strong stimulus
What are nodes of Ranvier?
Parts along the axon devoid of myelin
Hypercalcemia effect of transmission of action potential
Inhibits transmission by preventing opening of sodium gates during depolarization
Hypocalcemia effect of transmission of action potential
Makes nerve more irritable (Chvostek sign)
Ruffini endings:
Group
Location?
Function?
Group 1
Deep subcutaneous tissue
Joint position sens
Muscle spindles:
Group
Location?
Function?
Group Ia
in muscle
Detect changes in length of muscle
Golgi Tendon Organs:
Group
Location?
Function?
Group Ib
Tendons/Joints
Detect load/tension
Pacinian Corpuscles:
Group
Location?
Function?
Group II
Deep subcutaneous tissue and joints
Vibration
Meissner’s corpuscles:
Group
Location?
Function?
Group II
Dermal papillae
2-pt touch discrimination
Krause’s corpuscles:
Group
Location?
Function?
Group II
in dermis and cornea
Fine touch
Merkel cells:
Group
Location?
Function?
Group II
Epidermis
Crude touch and pressure
Naked nerve endings:
Group
Location?
Function?
Group III and IV
Skin and joints
Pain and temperature
CNS neurotransmitters that are excitatory? Inhibitory?
Excitatory: Glutamine, serotonin, ACh, Norepinephrine, dopamine
Inhibitory: GABA and glycine
PNS neurotransmitters?
ACH @neuromuscular junction, norepinephrine and Ch in ANS
where are cholinergic receptors found in the ANS and what type?
Neuromuscular junction - nicotinic
Postganglionic parasympathetic nerve endings - muscarinic
Adrenergic receptors in ANS, location and function: Alpha 1 Alpha 2 Beta 1 Beta 2 Beta 3
Alpha 1: smooth muscle in blood vessels, gut, sphincters, skin - constriction
Alpha 2: Islets of Langerhan’s - decrease insulin secetion
Beta 1: Cardiac muscle - increase rate and force and in kidney
Beta 2: Smooth muscle in bronchi, coronary vessels, skeletal muscle - dilation
Beta 3: In brown fat - increase lipolysis
A fiber nociceptors
Detect mechanical, cold and heat
Fast conduction, well-localized, sharp, pricking pain
C fibers
Somatic and visceral tissue, activated by thermal, chemical, mechanical stimuli with receptors for bradykinin, prostaglandin E2, serotonin, histamine, interleukin and TNF, slow conducting, poorly localized burning or dull aching pain
A alpha fibers diameter, speed, function, adaptation
12-20 um, 70-120 m/s, motor to skeletal muscle, slow
A beta fibers, group diameter, speed, function, adaptation
II, 5-12 um, 40-70 m/s, fine touch, vibration, proprioception, slow
A y fibers, group, diameter, speed, function, adaptation
Ia, 3-6 um, 10-50 m/s, muscle spindles, slow
A gamma fibers, group, diameter, speed, function, adaptation
III, 2-5 um, 6-30 m/s, fast pain, temperature, touch, RAPID