Purkinje fibres

Can you identify the purkinje fibres in this section?

The purkinje fibres are found in the sub-endocardium.

They are larger than cardiac muscle cells, but have fewer myofibrils, lots of glycogen and mitochondria, and no T-tubules. These cells are connected together by desmosomes and gap junctions, but not by intercalated discs.

They are specialised conducting fibres, which extend from the interventricular septum, to the papillary muscles, and up the lateral walls of the ventricles. More on contraction of the heart

em of purkinje cell

questionTake a look at this EM of a purkinje cell. How does it differ from that of a cardiac or muscle cell?

(Hint - how many myofibrils can you see?)