GENERAL HISTOLOGY

Detailed explanation-1: -A Nissl body is also known as Nissl substance is a large granular body found in neurons. These granules are rough endoplasmic reticulum (RER) with rosettes of free ribosomes and are the site of protein synthesis. These are present in the cell body of the nerve cell.

Detailed explanation-2: -In cellular neuroscience, Nissl bodies (also called Nissl granules, Nissl substance or tigroid substance) are discrete granular structures in neurons that consist of rough endoplasmic reticulum, a collection of parallel, membrane-bound cisternae studded with ribosomes on the cytosolic surface of the membranes.

Detailed explanation-3: -In living neurons, they are visible in phase contrast microscopy. The Nissl bodies represent the protein-synthetic machinery of the cell. Key constituents are ribosomes; they disappear in toluidine blue preparations after treatment with RNAase.