REVIEW: Nitric Oxide Cycle in Mammals and the Cyclicity Principle

V. P. Reutov

Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, ul. Butlerova 5a, Moscow, 117485 Russia; fax: (095) 338-8500; E-mail: valreutov@mtu-net.ru

Received February 22, 2001; Revision received September 4, 2001

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This paper continues a series of reports considering nitric oxide (NO) and its cyclic conversions in mammals. Numerous facts are summarized with the goal of developing a general concept that would allow the statement of the multiple effects of NO on various systems of living organisms in the form of a short and comprehensive law. The current state of biological aspects of NO research is analyzed in term of elucidation of possible role of these studies in the system of biological sciences. The general concept is based on a notion on cyclic conversions of NO and its metabolites. NO cycles in living organisms and nitrogen turnover in the biosphere and also the Bethe nitrogen-carbon cycle in star matter are considered. A hypothesis that the cyclic organization of processes in living organisms and the biosphere reflects the evolution of life is proposed: the development of physiological functions and metabolism are suggested to be closely related to space and evolution of the Earth as a planet of the Solar System.

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KEY WORDS: nitric oxide, NO synthases, nitrites, nitric oxide cycle, cyclicity principle

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