The Effect of Coenzyme Q on the Histochemical Succinic Tetrazolium Reductase Reaction: A Histochemical Study

Abstract

The role played by coenzyme Q (CoQ) in the succinic tetrazolium reductase reaction was investigated. Fresh cryostat sections of normal rat tissues were extracted with acetone to remove CoQ from the tissue sections and the acetone-extracted sections were reconstituted with CoQ-lecithin complexes. The incubation film method for tetrazolium reductases was used as a test system, using succinate as a substrate. Sections from which CoQ had been selectively extracted did not reduce the tetrazolium to its formazan, whereas those acetone-extracted sections that were treated with CoQ-lecithin complexes or with the electron carrier phenazine methosulfate reacted positively. It was concluded that the succinic tetrazolium reductase reaction requires intermediate electron carriers, mainly CoQ. It follows that nitro blue tetrazolium cannot accept electrons directly from the flavins. Therefore, the tetrazolium reductase reaction depends not only on the amount of succinic dehydrogenase and flavins but also on the amount of CoQ in the tissue.

HISTOCHEMICAL STUDY ON THE INTRAVITAL REDUCTION POTENCY OF COENZYME Q IN THE RESPIRATORY CHAIN OF THE HAIR CELLS OF THE SPIRAL ORGAN IN NORMAL GUINEA PIGS AND ITS ALTERATION IN ACUTE STARVATION AND VITAMIN B₁ DEFICIENCY

“…The enzymatic tetrazolium reducing reaction was carried out at 37°C for 15 minutes after various procedures for control. On the other hand, the effects of the extraction of CoQ and lipid, and restoration with CoQ on the succinate tetrazolium reductase reaction were investigated in the specimens of the spiral organ : for the extraction of CoQ aqueous acetone dilution (96%) was used as prefixative bath according to Horwitz et al (1967) (6) and for restoration of CoQ CoQ7 (suspension in distilled water, Takeda Chemical Industries, Ltd.) was added to the acetone-extracted specimens. The incubation medium for SDH consisted of: 5 ml sodium succinate (0.2 M) in distilled water; 5.0 ml phosphate buffer (0.2 M, pH 7.6) ; 10.0 ml Nitro-BT (1 mg/ml) in distilled water.…”

“…On the other hand, Klingenberg and Kroger (1967) (7) reveal that the function of CoQ in the respiratory chain is to form a collecting pool for hydrogen from the various dehydrogenases. Horwitz et al (1967) (6) suggest that CoQ acts as essential electron carrier in the succinate tetrazolium reductase reaction in fresh cryostat sections of the rat organs. The present authors also confirmed the role of CoQ Fin.…”

“…Crane et al (1959) (1), and Lester and Fleischer (J961) (2) developed a simple efficient method for removing Coenzyme Q (CoQ or ubiquinone, UQ) from mitochondria) preparation and for restoration with CoQ and clarified the role of CoQ as well as lipid in the electron transport system. Thereafter the effects of CoQ on the histochemical reaction for the activity of succinate dehydrogenase (SDH) in the tissue sections were intensively studied by Wattenberg and Leong (1960) (3), Straud and Wattenberg (1962) (4), Wolman and Bubis (1967) (5) and Horwitz et al (1967) (6). Horwitz et al (1967) (6)) studied the role of CoQ in the succinate tetrazolium reductase reaction in the fresh cryostat sections of normal rat tissues aftre acetone extraction of CoQ and restoration with CoQ lecithin complex.…”

“…Thereafter the effects of CoQ on the histochemical reaction for the activity of succinate dehydrogenase (SDH) in the tissue sections were intensively studied by Wattenberg and Leong (1960) (3), Straud and Wattenberg (1962) (4), Wolman and Bubis (1967) (5) and Horwitz et al (1967) (6). Horwitz et al (1967) (6)) studied the role of CoQ in the succinate tetrazolium reductase reaction in the fresh cryostat sections of normal rat tissues aftre acetone extraction of CoQ and restoration with CoQ lecithin complex. They concluded that the succinate tetrazolium reductase reaction requires intermediate electron carrier, mainly CoQ and nitro blue tetra-zolium (Nitro-BT) cannot accept electrons (or hydrogen atomes) directly from the flavins but from the intermediate electron carriers including CoQ.…”

Ultrastructural cytochemical identification of peroxisomes as organelles of terminal oxidation in amitochondrial trichomonad flagellates

“…Mitochondrial flavoprotein localization Tetrazolium reduction to insoluble, electron-dense, blue and purple formazans suitable for both light and electron microscope detection, by mitochondria and peroxisomes is attributable to flavoprotein enzymes (Brodie and Gots, 1952;Lester and Smith, 1961) or to flavoproteins plus a natural or artificial electron carrier corresponding to the link between flavoprotein and cytochrome b in the electron transport chain (Vitamin K, Slater, 1959;Coenzyme Q, or phenazine methyl sulfate (PMS) Horowitz et al, 1967). Only three mitochondrial flavoprotein systems are subject to tetrazolium localization:…”