Involvement of Metallothioneins in Regulation of Macrophage Activity after Combined Radiation and Thermal Injury

E. I. Khlopovskaya,¹ R. S. Budagov,¹ O. A. Smoryzanova,¹ and G. M. Rott^1,2

¹Medical Radiological Research Center, Russian Academy of Medical Sciences, ul. Koroleva 4, Obninsk, Kaluga Region, 249020 Russia; fax: (7-095) 956-14-40; E-mail: indep@mrrc.obninsk.su

²To whom correspondence should be addressed.

Submitted October 18, 1995; revision submitted November 18, 1996.

The levels of reduced metallothioneins (MT) in peritoneal macrophages and liver cells of mice subjected to combined radiation and chemical injury displayed opposite changes: the macrophage level of MT decreased and the liver MT increased. Simultaneously, there was an increase in luminol- and lucigenin-dependent chemiluminescence of phagocytizing macrophages. Stimulation with CdCl₂, a MT inducer, for three days before the injury increased the levels of MT in macrophages but decreased its liver levels. This effect was accompanied by a decrease in the intensity of the luminol-dependent but not lucigenin-dependent chemiluminescence. Administration of CdCl₂ after the injury facilitated the induction of reduced MT in liver cells; however, its level in macrophages remained low, and the intensity of their chemiluminescence did not decrease. The data suggest that MT is involved in oxidative metabolism and regulation of macrophage activity after combined radiation and thermal injury.

KEY WORDS: macrophages, chemiluminescence, combined radiation and thermal injury, metallothioneins, antioxidant defense.

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