The oxidation of glutaraldehyde by rat tissues.

Glutaraldehyde is used in pediatric dentistry as an alternative to formocresol in the treatment of primary teeth with diseased pulpal tissue. Because of concerns about the effects of glutaraldehyde in biological systems, the metabolism of ’4C (1, 5) glutaraldehyde (2.28 mC/mmole) in rat tissues investigated. Tissue slices prepared from liver, heart, kidney, and muscle were incubated in Krebs-Ringer bicarbonate buffer in the presence of ~4C-glutaraldehyde (800,000 DPM); the ~4C02was measured. The DPM ~4C02 (mean + SD) produced/400 mg slices (wet weight)~2 hr in liver, heart, kidney, and muscle were 16,385 +_3124, 5000 +_ 1217, 38,622 +_ 6233, and 1774 +_ 265, respectively. A 10,000 g "mitochondrial" subfraction was prepared from kidney and incubated with glutaraldehyde (100,000 DPM). The production of~4C02 was linear for 15 min and up to 5 mg protein. It is concluded that glutaraldehyde can be metabolized in living systems. Concern over the clinical use of formocresol as a pulpal fixative stems from doubts about its clinical effectiveness (Magnusson 1978), local irritating effects (Block et al. 1978), systemic absorption (Pashley et 1980), and toxicity (Lewis and Chestner 1981). Glutaraldehyde has been suggested as the potential pulpotomy agent of choice to replace formocresol (Davis et al. 1982) in the dental armamentarium. A popular dentin primer called Gluma, which is used prior to composite bonding, contains 5% glutaraldehyde (Munksgaard et al. 1985). Although glutaraldehyde, a bifunctional reagent, is an effective protein cross-linking agent and, therefore, a powerful fixative (Dawes 1979; Ranly and Lazzari 1983), little information is available concerning the metabolism of this compound in the body (Horton 1977). This paper presents data on the metabolism of glutaraldehyde in rat tissue. Materials and Methods