Large-section cryomicrotomy for in vitro receptor autoradiography

Area of Science:

• Neuroscience
• Histology
• Biochemistry

Background:

• Autoradiography is a powerful technique for visualizing the distribution of radiolabeled molecules in biological tissues.
• Processing large human postmortem tissue sections for autoradiography presents technical challenges, particularly in maintaining tissue integrity and section quality.

Purpose of the Study:

• To develop and describe a novel method for processing human postmortem material for autoradiography on large cryosections.
• To demonstrate the applicability of this method to whole organs and muscles.

Main Methods:

• Human postmortem whole organ or tissue slices (5 mm thick) were frozen using liquid nitrogen-cooled copper plates.
• Tissues were embedded in carboxymethyl-cellulose, and 40- to 80-micron sections were prepared.
• Sections were mounted on adhesive tape and paper, then transferred to gelatinized glass plates for incubation.

Main Results:

• The method successfully produced autoradiographs of large human brain hemisphere sections using [3H]quinuclidinylbenzilate.
• Autoradiographs of whole human biceps muscle sections using [3H]alpha-bungarotoxin were also successfully generated, demonstrating the method's versatility.

Conclusions:

• The described method provides a reliable approach for preparing large human postmortem cryosections for autoradiography.
• This technique enhances the ability to study molecular distributions in intact human tissues, advancing research in neuroscience and muscle biology.