The PubMed database contains more than 80,000 references related to the problem of the inflammation in medicine and biology. Nevertheless, the studies dedicated to the problem of inflammatory response do not loose their pertinence and keep top positions on the ranking of the most important scientific directions.
The physiology of inflammation is very complicate. There are five universal hallmarks of the inflammation, four of theme were described by Celsus in the Ancient Rome as follows tetrad: rubor (i.e. hyperemia or redness due to increased blood flow), calor (heat due to increased metabolic activity and blood flow), tumor (i.e. swelling or oedema), and dolor (i.e. pain). The fifth hallmark of the inflammation was added to the previous by Dr. Rudolf Virhow only in the middle of XIX century. This is "functio laesa" or loss of function. But these visible indices of the inflammation are the result of the sophisticated processes mediated by the numerous humoral and cellular factors (Ley, 2001).
Thus there is well known, that the inflammatory response has two components - cellular and exudative. The exudation is characterized by producing exudates i.e. fluids and cellular substances that are slowly discharged from blood vessels of inflamed tissues. The exudates contain proteins (fibrin and others) and could be released due to the increase of capillary permeability in the affected tissue. This process leads to the occurrence of oedema, thus by the measurement of swelling area the researcher can control the intensity of the inflammation. There is also important to remember that oedema distends the tissues, irritate the nervous receptors and can cause pain (Ley, 2001).
The cellular component of the inflammation is presented by the emigration of leucocytes from the blood vessels into the inflamed tissues. Nevertheless for the research planned and conducted by the schedule of our training there is more important to recognise main mediators of the inflammation.
There was demonstrated in the studies conducted recently (Ley, 2001; Sigal, 2005; Hildebrand, Pape & Krettek, 2005) that cytokines interleukin-1 and tumor necrotizing factors can play important role in the upregulation of the endothelial receptors and the processes of extravasation (i.e. e,igration of inflammatory cells into extravascular sites). This can increase intensity of swelling also.
The vasoactive agents can influence on the processes of the exudation and extravasation significantly. Nevertheless they role are not studied completely. In the last decades the researchers pais great attention to the mechanisms of the impact of some vasoactive peptides on the microvascular responses during the acute and chronic inflammation. There are many candidates for profound studies in this area, nevertheless, some investigators prefer to use calcitonin gene-related peptide (CGRP) for modelling physiological reactions during the inflammatory response. This is a 37 amino acid peptide that is produced in the central and peripheral nervous system in the rodents (rats and mice). Since 1985 (Brain et al) there is known that CGRP is an extremely potent and long lasting microvascular vasodilator which can act to potentiate