Demonstration of intracellular structures by high resolution scanning electron microscopy

Area of Science:

• Cell Biology
• Microscopy
• Structural Biology

Background:

• Understanding the intricate three-dimensional (3D) structure of intracellular components is crucial for elucidating cellular function.
• Previous imaging techniques have limitations in resolving the fine details of organelle architecture.

Purpose of the Study:

• To visualize and characterize the 3D ultrastructure of key intracellular elements using high-resolution field emission scanning electron microscopy (FE-SEM).
• To provide detailed morphological insights into the rough endoplasmic reticulum, Golgi complex, and synaptic vesicles.

Main Methods:

• Utilized the Osmium-DMSO-Osmium method for sample preparation.
• Employed a field emission scanning electron microscope (FE-SEM) with high-resolution capabilities for direct observation.
• Performed direct magnification ranging from 100,000x to 200,000x for synaptic vesicle analysis.

Main Results:

• Detailed 3D structure of rough endoplasmic reticulum cisternae, lamellar systems, and connections to the cell membrane were observed.
• Characterized the bell-shape and unique foot-like tubuli of Golgi cisternae in rat submandibular gland serous cells.
• Described the size (30-50 nm), varied shapes (spherical, cocoon-like, kidney-shape), and granular content (approx. 10 nm) of rat retinal synaptic vesicles.

Conclusions:

• FE-SEM provides unprecedented 3D structural detail of intracellular organelles.
• The observed morphologies of the rough endoplasmic reticulum, Golgi complex, and synaptic vesicles offer new insights into their organization and potential functions.
• Further investigation into mitochondria and centrioles using this technique is warranted.