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| * The nucleus remains normal. | | * The nucleus remains normal. |
| ** Nuclear changes are only seen if the degree of fatty change becomes incompatible with the continued existence of the cell. | | ** Nuclear changes are only seen if the degree of fatty change becomes incompatible with the continued existence of the cell. |
− | To decide whether or not a vacuole in the cytoplasm of a hepatocyte is fat ( because there are
| + | * In hepatocytes, it is necessary to stain for fat in order to ellucidate if a vacuole in the cytoplasm is fat-containing. |
− | two further conditions which may produce vacuoles in hepatocytes, namely the vacuolar
| + | ** Two further conditions may produce vacuoles in hepatocytes. |
− | hydropic degeneration mentioned before and also the accumulation of glycogen ), it is | + | *** [[General Pathology#Vacuolar Degeneration|Vacuolar hydropic degeneration]] |
− | necessary to stain for the fat present. There are a variety of stains and common ones are
| + | *** Glycogen accumulation |
− | Sudan 111, Sudan 1V, and Oil Red O which stain fat varying shades of orange to red. | + | ** Stains commonly used include Sudan 111, Sudan 1V, and Oil Red O. |
− | It is necessary to prepare the sections differently to the routine paraffin embedding as per
| + | *** Stain fat varying shades of orange to red. |
− | H&E. This is because in paraffin embedding, the fat is dissolved out of the cell by the strong | + | ** Sections must be prepared differently to the routine paraffin embedding (used e.g. in H&E staining). |
− | solvents employed. To get over this problem, the block of tissue to be examined is frozen
| + | *** The strong solvents used in paraffin embedding dissolve the fat out of the cell. |
− | and sectioned in a cryostat (a cabinet containing a microtome and kept at - 20 0 C), before | + | *** When staining for fat, the tissue to be examined is frozen and sectioned in a cryostat before being stained. |
− | being stained. | + | **** These sections are more than twice as thick as those attained by sectioning paraffin blocks |
− | These sections are over twice as thick as those attained by sectioning paraffin blocks, and so | + | ***** There may be some overlap of cells on the section. |
− | there may be some overlap of cells on the section, and less clarity of the individual cells.
| + | ***** Individual cells are less clear. |
| | | |
| ====Causes of Fatty Change==== | | ====Causes of Fatty Change==== |