A comparative study in the transmission electron microscope and scanning electron microscope of intracellular structures in sheep heart muscle cells

Abstract

SUMMARY The internal cellular structures of the sheep ventricular myocardium have been comparatively studied in the transmission electron microscope (TEM) and in the scanning electron microscope (SEM). For TEM studies the tissue was prepared according to standard methods. Thick sections (10 μm) of paraffin embedded material were, after they had been deparaffinized in toluene, critical point dried, coated with gold and examined in the SEM. The comparative TEM and SEM investigations revealed very good correspondence, and it is evident that the described preparation procedure for SEM has preserved the fine structures of myofibrils, mitochondria, T‐Tubules and sarcoplasmic reticulum in an excellent life‐like pattern. Of special interest was the three‐dimensional demonstration of triads and of circumferentially arranged T‐tubules.

Cryofracture of paraffin‐embedded heart muscle cells

“…McCallister et al (1 974) described circumferentially arranged T-tubules in the rat myocardial cell. Similar structures were also observed by Myklebust et al (1975) in the sheep myocardial cell. However, the present study does not favour the interpretation of these structures as T-tubules.…”

“…However, due to considerable shrinkage associated with air-drying (Boyde & Wood, 1969), the preservation of the internal cell structures was rather poor. This problem was later overcome by substituting air-drying with critical point drying using Freon 13 (Sybers & Ashraf, 1973) or COz (Myklebust et al, 1975). Applying this modification, these authors reported a very good preservation of the intracellular structures of the myocardial cell.…”

“…Unfortunately, this dehydration procedure is associated with a severe shrinkage of soft tissue (Boyde & Wood, 1969). To overcome this problem air-drying has been substituted by critical point drying of the sections (Myklebust et al, 1975;Sybers & Ashraf, 1973), which maintained the cell organelles in a life-like pattern. An alternative technique has been to utilize sectioned Epon-embedded material (Erlandsen et al, 1973;Lange & Kegel, 1972;Pachter et al, 1973a), which after removal of the polymerized epoxy resin with an appropriate solvent was studied in the SEM.…”

Steedman's polyester wax embedment and de‐embedment for combined light and scanning electron microscopy

“…Several investigators have tried the "obvious" approach of using paraffin wax to obtain specimen orientation or to combine LM and SEM (McDonald et al, 1967;Myklebust et al, 1975;Pattee et al, 1984). This report details a similar approach, using polyester wax (Steedman, 1957(Steedman, , 1960Sidman et al, 19611, which we find to be quite suitable for de-embedding and whose properties we believe make it more desirable than paraffin for routine histology.…”

Ultrastructure Of Cell Organelles By Scanning Electron Microscopy Of Thick Sections Surface‐Etched By An Oxygen Plasma

“…ethanol, acetone, Freons) followed by cryofracturing, thawing the fractured tissue in the intermediate fluid, and critical point drying (Sybers & Ashraf, 1973;Humphreys et al, 1973bHumphreys et al, , 1974Miyai et al, 1976;Munger &Mumaw, 1976) has become a valuable technique that has provided a new and very useful way of looking inside tissues with the scanning electron microscope. Myklebust et al (1975) studied the ultrastructure of heart muscle by scanning electron microscopy of deparaffinized, critical point dried thick sections of paraffin-embedded tissue. In none of these studies was the internal structure of organelles such as the cristae of mitochondria clearly visible.…”