Receptor localization of steroid hormones and drugs: discoveries through the use of thaw-mount and dry-mount autoradiography

Abstract

The history of receptor autoradiography, its development and applications, testify to the utility of this histochemical technique for localizing radiolabeled hormones and drugs at cellular and subcellular sites of action in intact tissues. Localization of diffusible compounds has been a challenge that was met through the introduction of the "thaw-mount" and "dry-mount" autoradiographic techniques thirty years ago. With this cellular receptor autoradiography, used alone or combined with other histochemical techniques, sites of specific binding and deposition in vivo and in vitro have been characterized. Numerous discoveries, some reviewed in this article, provided information that led to new concepts and opened new areas of research. As an example, in recent years more than fifty target tissues for vitamin D have been specified, challenging the conventional view about the main biological role of vitamin D. The functions of most of these vitamin D target tissues are unrelated to the regulation of systemic calcium homeostasis, but pertain to the (seasonal) regulation of endo- and exocrine secretion, cell proliferation, reproduction, neural, immune and cardiovascular responses, and adaptation to stress. Receptor autoradiography with cellular resolution has become an indispensable tool in drug research and development, since information can be obtained that is difficult or impossible to gain otherwise.

Comparison between thaw-mounting and use of conductive tape for sample preparation in ToF-SIMS imaging of lipids in Drosophila microRNA-14 model

“…[30][31][32] For example, cholesterol, mucopolysaccharides (long chains of sugar), and other extracellular components undergo some degrees of diffusion during thaw-mounting, which has been reported in previous literature. [33][34][35] Moreover, the thaw-mounting method has been unable to produce subcellular resolution of tissues with small cells and high cell density, such as the pituitary gland, lymph nodes, and even livers, but the subcellular images of these tissues were obtained using the tape-supporting method. 29,36,37 To confirm this, we prepared samples using both the thaw-mounting and adhesive tape-supporting methods.…”

Localizing estradiol and other diffusible hormones and drugs by autoradiography and immunocytochemistry

“…Freeze-mounting of unfixed and unembedded tissue, thin frozen sectioning, and thaw-mounting (controlled by dry-mounting) on dry photographic emulsion are crucial steps toward achieving authentic cellular-subcellular localization of diffusible compounds. By comparison, this procedure is neither "laborious" nor "labor-intensive", as sometimes misjudged, but simple, sensitive, and expedient as documented by the many successful applications and discoveries made with this technique (Stumpf 1998).…”