Study on Conformational Changes in Hemoglobin Protoporphyrin in Essential Hypertension

G. V. Maksimov^*, N. V. Maksimova, A. A. Churin, S. N. Orlov, and A. B. Rubin

Department of Biology, Lomonosov Moscow State University, Moscow, 119899 Russia; fax: (095) 939-1115; E-mail: maxim@biophys.msu.ru

^* To whom correspondence should be addressed.

Received February 8, 2000; Revision received August 29, 2000

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Changes in protoporphyrin conformation, partial pressures of O₂ and CO₂, and the mechanisms responsible for regulation of pCa and pH in erythrocytes were studied in essential hypertension (EH). Changes in protoporphyrin conformation in EH were accompanied by a decrease in the partial pressure of O₂ and an increase in the partial pressure of CO₂. This was associated with increased activities of Na⁺/H⁺-exchange and Ca²⁺-dependent K⁺-channels and with a decreased activity of Ca²⁺-ATPase. The changes in protoporphyrin conformation in EH are suggested to decrease the efficiency of O₂ metabolism in hemoglobin and increase the values of intracellular pCa and pH of erythrocytes.

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KEY WORDS: protoporphyrin conformation, Raman-spectroscopy, Na⁺/H⁺-exchange, Ca²⁺-dependent K⁺-channel, Ca²⁺-ATPase, essential hypertension

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