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Updated: May 6, 2026
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An Ex vivo Culture System to Study Thyroid Development
Published on: June 6, 2014
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Preparation and properties of thyroid cell membranes
J B Stanbury1, J V Wicken, M A Lafferty
1Department of Nutrition and Food Science, Massachusetts Institute of Technology, 02139, Cambridge, Massachusetts.
The Journal of Membrane Biology
|November 1, 2013
Summary
Nitrogen microcavitation separated calf and human thyroid membranes. A lighter fraction, enriched in plasma membrane fragments, showed higher enzyme activity than the heavier fraction.
Area of Science:
- Biochemistry
- Cell Biology
- Membrane Biology
Background:
- Thyroid membranes play crucial roles in hormone synthesis and secretion.
- Understanding membrane composition is essential for elucidating thyroid function.
Purpose of the Study:
- To isolate and characterize different thyroid membrane fractions.
- To identify specific membrane components associated with distinct cellular origins.
Main Methods:
- Thyroid tissues (calf and human) were disrupted using nitrogen microcavitation.
- Membranes were prepared through repeated centrifugation in low ionic strength buffers.
- Two membrane fractions were obtained using ficoll density gradient centrifugation.
Main Results:
- A lighter membrane fraction, consisting of larger vesicles, exhibited higher activities of Na(+)-K(+)-activated ATPase, phosphodiesterase, and 5'-nucleotidase.
- A heavier membrane fraction displayed greater nicotinamide adenine nucleotide dehydrogenase-diaphorase activity.
- Enzyme activity profiles suggest the lighter fraction is enriched in plasma membrane fragments.
Conclusions:
- Nitrogen microcavitation and differential centrifugation effectively separate thyroid membrane components.
- Distinct enzyme activities correlate with specific membrane fractions, aiding in plasma membrane identification.
- This fractionation method provides a basis for further biochemical studies of thyroid plasma membranes.
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