Intrinsic cardiac neuron cultures. Panels A and B are representative of normal neuronal cells in culture identified via phase contrast microscopy. Panel A demonstrates STZ-diabetic rat neurons at 48 hours in culture. Panel B demonstrates age-matched control rat neurons at 48 hours in culture. Several different neuronal types were isolated, including large pseudounipolar appearing cells similar to dorsal root ganglion cells (thin arrows), as well as bi- (arrowheads) and multi-polar (thick arrows) cells indicative of efferent or interneuronal cell types.