Isolation of liver nuclei that retain functional trans-membrane transport.

We have developed a method for the rapid isolation of hepatocyte nuclei, which employs gentle homogenization and centrifugation conditions, and involves minimal processing time. The purified nuclei were morphologically unaltered when observed by light and electron microscopy. No significant contamination from cytoplasm or mitochondria was detected when assessed by marker enzymes. Membrane transport function, measured as ATP-dependent calcium uptake, was intact. This isolation method was devised to be applicable to studies that involve measurement of uptake and active transport of a variety of substances by the cell nucleus.