Morpho-functional features of Hirudo verbana after girudotherapeutic procedure

Abstract

In the real scientific period hirudotherapy is one of the leading methods of the traditional medicine. The body of the medicinal leech produced unique natural complex of biologically active substances (BAS), which arrive independently in the human or animal body during bite. Therefore leech is the ideal instrument in a soling for a big amount of the endoecological problems. Medicinal leeches – a blood-sucking ectoparasites. They have a relative specialization: a well-developed nervous system, sensory organs, muscles. The characteristics of the digestive system deep specialization are the structure of the jaws, the presence of salivary glands with a secret containing BAS, folds in the crop and others. The endosymbiotic bacterium Aeromonas hydrophila is present in gastrointestinal tract of the leech. It plays a major role in the digestion of proteins, fats and carbohydrates. It is involved in the maintenance of liquid state of the ingested blood. These adaptive mechanisms show physiological conditioning of the medicinal leeches lifestyle as free-living ectoparasites. Not all medicinal leeches overcome immunological and bacterial during feeding of the blood of native mammals, which in additional antigenic load. Some leeches can not cope with digesting food and die. The researches about the death of leeches are absent in the present scientific literature. There are no information about morphological changes in the organs of H. verbana after girudotherapeutic procedure.

Purpose: The study of the morphofunctional peculiarities of internal organs and tissues in medicinal leech (H. verbana) after feeding of native human blood.

Materials and methods. The experiment was carried out with mature specimens of the H. verbana in the age of 7 months, divided into 2 groups of 15 animals in each: 1) control group — hungry leeches, which were fed 3 months ago, 2) fed intact leeches after human blood feeding. Histological sections were made with anterior, middle, posterior thirds of the body. They olso were stained with hematoxylin and eosin and Schiff-reagent with hematoxylin. Histological and histochemical features of the leeches body structure were analized, special attention was paid to the structural and functional characteristics of the digestive system (stomach crop) and the surrounding connective and botrioidal tissue.

Results. It was established that intestinal epithelium and surrounding botrioidal tissue are in an inactive state in hungry leech. Morpho-functional changes in the midgut of H. verbana after feeding are expressed in changes of the epithelium height due to excessive stretching with blood filling, in changes of its carbohydrate composition and the level of vacuolization. Botrioidal tissue of leeches after feeding reacts to the receipt of digestion products in increase of the vascularization, increase of levels of carbohydrates containing substances accumulation, activation of some botrioidal granulocytes. These features are the result of normal physiological processes — absorption and accumulation of plastic materials.

Conclusions

1. Morphofunctional changes in the midgut (crop) H. verbana after 12 days of human blood feeding is in the change of the epithelium height due to excessive stretching during blood filling, in changes of its carbohydrate composition and level of vacuolization.

2. Botrioidal tissue of leeches after feeding reacts to the receipt of digestion materials in increase of vascularization, of levels of carbohydrates’ containing substances accumulation, activation of some botrioidal granulocytes.

3. These features are the result of normal physiological processes — absorption and accumulation of plastic materials.

4. We considers, that further histological and histochemical studies related to morphological changes in the organs of leeches with the pathological response to blood feeding, which leads to the leeches death, are perspective.