Histological Staining Methods

In this chapter we shall examine the development and application of histological methods at the tissue and system level of neural organisation. The principal techniques — fixation, dyeing, metal impregnation and histochemistry — have already been encountered in Chapter 1, where the emphasis was at the cytological level. The two chapters are intended to be considered together, thus the specific techniques covered in each one are applicable at both cellular and tissue levels. Once again, the methods to be described here will, whenever possible, be placed in the context of particular functional problems. There are, however, no hard and fast rules about which is the most appropriate method to apply to a given problem; this will depend on many factors not all under the investigator’s control, including one’s experience, material resources and availability of imaging and data-recording facilities. Of course, it should be borne in mind that different methods will almost certainly generate somewhat different data while addressing the same problem. This point will be illustrated in example 4 below with a case study from my own work on the innervation of muscle spindles.