Histological techniques

Histological technique is a set of ways of processing of biological objects (cells, tissues, organs) to study their microscopic structure.
Living tissues available direct observation in vivo conditions and in tissue culture, when the pieces of bodies are grown in artificial nutrient environment or in the body of experimental animals (for example, in the subcutaneous tissue).
To study the fixed drug use slices of tissue and organ obtained during surgery or autopsy. To study take more fresh material. Researched pieces of cloth should not be large, otherwise fixing the liquid will penetrate their thick. In the preparation of drugs should prevent shrinkage and deformation of the pieces, especially shells.
Fixation of the object of research is one of the most important stages of processing. Correct record of tissues facilitates subsequent histological processing, allows us to preserve the structure of the objects and to prevent its changes. The most common clips - solutions formalin, alcohol, chromates, osmaeva acid, as well as their various combinations. Declinatio objects (bones, teeth) are solutions of nitric, hydrochloric, formic acid. Degreasing is achieved by processing objects in the spirits rising fortress, carboxylase, ether and chloroform. Processed pieces subjected to compaction by including them in paraffin, celloidin, gelatine.
After sealing stripes (the thickness of 3-15 MK) are made on the microtome(see). Sections flow objects get on freezing microtome.
For better identification details of the structure of the pieces or slices paint. Used in histological techniques dyes are divided into acidic, basic and neutral. The most common hematoxylin, eosin, Carmine, Magenta, Azur, toluidine blue, Congo red. Selective detection of tissue structures is achieved also by impregnation (impregnation) of their salts of heavy metals (nitrate silver, chlor gold, osmium, lead).
A special place is occupied methods histochemical studies, which allows to study metabolic processes in tissues. The most important methods of historiografii, giving the opportunity to investigate the dynamics of structural changes.