Nerve Physiology (Part - 2) Action potential, Refractory Period, and Resting Membrane Potential

📌𝗙𝗼𝗿 𝗡𝗼𝘁𝗲𝘀 𝗢𝗳 𝗧𝗵𝗶𝘀 𝗦𝗲𝘀𝘀𝗶𝗼𝗻 𝗝𝗼𝗶𝗻 𝗺𝘆 𝗧𝗲𝗹𝗲𝗴𝗿𝗮𝗺 𝗰𝗵𝗮𝗻𝗻𝗲𝗹 𝗵𝗲𝗿𝗲:-​ https://telegram.me/bhanuprakashdr​
📌 𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦:-   / drgbhanuprakash  
📌𝗦𝘂𝗯𝘀𝗰𝗿𝗶𝗯𝗲 𝗧𝗼 𝗠𝘆 𝗠𝗮𝗶𝗹𝗶𝗻𝗴 𝗟𝗶𝘀𝘁:- https://linktr.ee/DrGBhanuprakash

Nerve Physiology : Structure and Types of Neurons, Blood brain barrier, Resting membrane potential

Structure and Types of Neurons

Structure of a Neuron
_____________________
Cell Body (Soma): Contains the nucleus and essential organelles.
Dendrites: Branch-like extensions that receive signals from other neurons.
Axon: Long projection that transmits signals to other neurons or muscles.
Myelin Sheath: Fatty insulation that increases signal transmission speed.

Types of Neurons
__________________
Sensory Neurons: Transmit sensory information from receptors to the CNS.
Motor Neurons: Transmit motor information from the CNS to effectors (muscles, glands).
Interneurons: Located within the CNS and connect sensory and motor neurons.

Blood-Brain Barrier (BBB)
_________________________
Structure and Composition: Made of tight junctions between endothelial cells of cerebral capillaries.
· Astrocyte foot processes reinforce the barrier.
Function
· Protects the brain from harmful substances in the blood.
· Regulates transport of nutrients and waste products.
· Blocks many drugs, bacteria, and large molecules.
Clinical Relevance: Alterations or breakdown of the BBB can lead to neurological disorders.

Resting Membrane Potential (RMP)
___________________________________
Definition: The electric potential across the cell membrane at rest, typically -70mV in neurons.

Mechanism
· Sodium-Potassium Pump (Na+/K+ Pump):

Pumps 3 Na+ out and 2 K+ in, creating a concentration gradient.
Requires ATP for energy.
· Potassium Leak Channels:
Allow K+ to flow out of the cell, following the concentration gradient.
Contributes to the negative inside relative to outside.
· Sodium Leak Channels:
Less permeable to Na+ than to K+, but some Na+ does leak into the cell.
· Balance of Forces:
The concentration gradient pulls K+ out and Na+ in.
The electrical gradient opposes this movement.
At rest, these forces are in equilibrium.
Clinical Relevance: Understanding RMP is crucial for understanding nerve impulse propagation, muscle contractions, and various neurological disorders.

#fmge #fmgevideos #rapidrevisionfmge #fmgejan2023 #mbbslectures #nationalexitexam #nationalexittest #neetpg #usmlepreparation #usmlestep1 #fmge #usmle #drgbhanuprakash #medicalstudents #medicalstudent #medicalcollege #neetpg2023 #usmleprep #usmlevideos #usmlestep1videos #medicalstudents #neetpgvideos #nervephysiology #rmp #restingmembranepotential #bloodbrainbarrier #neuron #neurons #neurontypes #nervephysiology #mbbslectures #nervephysiology