title: Dithiocarbamylation in histochemistry: carbon disulfide as a reagent for the visualization of primary amino groups with the light and electron microscope.
abstract: Tissue amino groups undergo dithiocarbamylation on treatment (12 hr, 22-25 degrees C) with a carbon disulfide:triethylamine:tetrahydrofuran (1:1:0.5, v/v) mixture. After washing with tetrahydrofuran:triethylamine (4:1, v/v) followed by tetrahydrofuran:pyridine (4:1,v/v) and ice-cold distilled water tissues were immersed into ice-cold 10% (w/v) lead acetate to yield yellowish lead dithiocarbamates. At 22-25 degrees C the derivatives obtained from primary amines decompose to lead sulfide. After washing with 5% lead acetate in 10% acetic acid followed by three changes of distilled water tissues are dehydrated and embedded in paraffin or Maraglas as usual. In proteins the reaction is given by the epsilon-amino group of lysine and alpha-terminal amino groups, while nucleic acids do not react. Results are shown in tetrahydrofuran-delipidized ethanol or formalin-fixed 1) plant root tips where brown-colored and electron-dense lead sulfide deposits are localized in condensed chromatin and chromosomes attributable to lysine-rich histones and 2) rat skeletal muscle where an interfibrillar component is visualized in a repeating pattern, possibly related to terminal regions of the sarcoplasmic reticulum.
mesh_terms: D000588:Amines / Q000032:analysis*; D000818:Animals; D002246:Carbon Disulfide; D002843:Chromatin / Q000648:ultrastructure*; D006651:Histocytochemistry; D008854:Microscopy, Electron / Q000379:methods; D009132:Muscles / Q000648:ultrastructure*; D010944:Plants / Q000648:ultrastructure*; D051381:Rats; D013859:Thiocarbamates
chemical_list: D000588:Amines; D002843:Chromatin; D013859:Thiocarbamates; D002246:Carbon Disulfide