Neuroglia cells

📌 Neuroglia
Non-neural cells represent the dominant part of the nervous system.

🖇 Characters:

• Small in size & numerous in number.
• Represent half of CNS volume.
• Highly divided by mitosis in tumor.
• All are ectodermal in origin except microglia → mesodermal

🟣 CNS Cells

1️⃣ Microglia

📍 Site:

• White & gray matter.

🚨 Function:

• Antigen presenting cells.
• هي الخلايا الوحيدة التي تنشأ من الميزوديرم.

🟠 Distinctive Features:

• Micro in size.
• Mesodermal in origin.
• Macrophage cells.

2️⃣ Astrocyte

📌 Astrocytes are divided into two types:

• Protoplasmic Cell : Large cell with large nucleus Numerous thick processes with branches.
• Fibrous Cell: Tall, thin process With non-branched processes

📌 EM (Electron Microscope):

• Golgi apparatus present.
• Presence of glial filaments, which are specific for this type (protoplasmic glia).

📌 Cytoplasm Characteristics:

• Electron lucent cytoplasm.
• Highly free organelles.

🚨 Function:

• Support.
• Nutrition.
• Metabolic activity.

3️⃣ Ependymal Glia

📍 Site:

• Spinal canal (القناة الشوكية).
• Brain ventricles (بطينات الدماغ).

🚨 Function:

• CSF formation.

4️⃣ Oligodendrocyte Glia Cells

📌 Types:

• Interfascicular: White matter → with axons.
• • النوع الموجود في المادة البيضاء بجوار المحاور العصبية (axons).
• Perineuronal: Gray matter → with soma.
• • النوع الموجود في المادة الرمادية حول جسم الخلية (soma).

📌 EM (Electron Microscope):
Cytoplasm contains:

• RER
• Golgi
• Mitochondria
• Lysosome
• Presence of Microtubules