The paper summarises the comprehensive concept on main groups of chemical substances and on their diverse regulatory function in the brain. Neurotransmitters, neuropeptides, neurotrophic and growth factors, and cytokines are considered as many-storied, integral structure. The proper analysis of ischemic and neurodegenerative brain disturbances evidently demonstrates the active participation of basic families of these chemical regulators at all stages of the pathogenesis. The main theoretical positions involving these regulatory substances in the control of normal and pathological situations include: (a) dogma on the imbalance of chemical regulators, as the initial pathogenetic principle; (b) genetically heterogeneity of brain structures, which demonstrate selective vulnerability or, to the contrary, steadiness for damaging exposure. As a general principle for increasing number of clinical and experimental pathologies, the induction of apoptic cascade processes is postulated; their "normal" biological function in nervous tissues is a key factor for development of majority of brain diseases.