Figure 4: (A) A photomicrograph of the SAN showing the second lobe of the SAN head having; P. cells (short arrow) and T. cells (long arrow) and the atrial purkinje like cell (arrow head) Stain: H&E Obj.x10 : Oc.x10. (B) showing the collagen fiber (long arrow), and the atrial purkinje like cell (arrow head) Stain: Green Masson's Trichrome Obj.x10: Oc.x10. (C) showing the SAN arm (short arrow), and the atrial purkinje like cell (long arrow) Stain: PAS Obj.x10: Oc.x10. (D) showing the P. cells (single arrow) and T. cells (arrow head) and the atrial purkinje like cell double arrows) Stain: Green Masson's Trichrome Obj.x40: Oc.x10. (E) showing the strongly PAS positive reaction of the atrial purkinje like cell (long arrow) Stain: PAS Obj.x40: Oc.x10. (F) showing P. cells (single arrow) and T. cells (arrow head) and the atrial purkinje like cell (double arrow) Stain: Jone's Methenamine Silver stain Obj.x40: Oc.x10.