CHAPTER 18 



The Isolation and Composition of Cell Nuclei and Nucleoli 

 ALEXANDER L. BOUNCE* 



Page 

 I. Methods of Isolating Cell Nuclei 94 



1. Methods Involving the Use of Aqueous Solutions 94 



a. Limitations of Methods 94 



b. Methods for Removing Fiber and Homogenizing Tissue 96 



c. Perfusion of Organs for the Removal of Blood 103 



d. Description of Methods 104 



(1) Methods Involving the Use of Citric Acid in Water Solution . . . 104 



(2) Methods Involving Solutions of Gum Arabic in Water 105 



(3) Methods Involving the Use of Sucrose in Water Solution .... 106 



(4) Methods Involving Aqueous Solutions of Ethylene Glycol, Glyc- 

 erol, or Poh'ethj'lene Glycol 108 



(5) Methods Involving the Use of Buffered or Unbuffered Salt Solution 109 



2. Methods Involving the Use of Nonaqueous Solvents with I.yophilized 

 Material 110 



a. Limitations of Methods 110 



b. Description of Apparatus for Lyophilizing Tissue Ill 



c. Description of Methods 113 



(1) Behrens' Original Procedure 113 



(2) Subsequent Modifications 114 



3. Comparison of Results Obtained Using the Various Methods Described 

 Above, and Choice of Method for the Particular Study Being Undertaken 116 



a. Overall Comparison of Results 116 



b. Choice of Method for Study of Lipids 117 



c. Choice of Method for Study of Nucleic Acids 118 



d. Choice of Method for Study of Proteins 118 



e. Choice of Method for Study of Enzymes 119 



f. Choice of Method for Study of Vitamins 119 



g. Choice of Method for Study of Minerals 119 



II. Chemical Composition of the Cell Nucleus 120 



1. Introductory Remarks 120 



2. Composition of the Nucleus with Respect to Lipid 120 



a. Total Lipid 120 



b. Individual Lipid Fractions 121 



* Support of the National Cancer Institute of the National Institutes of Health, 

 U. S. Public Health Service, is gratefully acknowledged. 



93 



