A preventive short-term hypoxia (preconditioning) increases neuronal resistance against subsequent strong hypoxic effects. Literature review and authors' own data on molecular-cellular mechanisms of the hypoxic preconditioning, are presented. Participation of intracellular signal transduction, genome, stress-proteins, and neuromodulating peptides in this process, is discussed. The role of glutamatergic as well as calcium and phosphoinositide regulatory systems and neuromodulating factors as the components of a "volume" signal transmission are analyzed in hypoxic precondition-associated induction of functional tolerance mechanisms against acute harmful effects in neurones of olfactory slices.