Binding of gentamicin to subcellular fractions of rabbit kidney: inhibition by spermine and other polyamines

Reduction of experimental gentamicin nephrotoxicity in rats by dietary calcium loading

“…As with cell membranes, intracellular membrane function may be modified by calcium. In support of that mechanism, calcium has previously been reported to reduce the binding of gentamicin to mitochondria (16). Its effect on lysosomal binding of gentamicin is not known.…”

“…Calcium has been reported to diminish aminoglycoside binding or transport by gram-positive and -negative bacteria (7), rabbit vascular smooth muscle (12), renal mitochondria (16), and human serum proteins (18). Furthermore, calcium in nutrient medium decreases in vitro gentamicin antibacterial activity (9) and is also reported to reverse or prevent an aminoglycoside-mediated neuromuscular blockade (16).…”

Peripheral inactivation of gentamicin

“…This problem has been approached in vitro either by incubating purulent material with gentamicin (Bryant & Hammond, 1974;Davis & Bruns, 1978) or, by testing different groups of purified macromolecules for gentamicin (Deguchi, Ishii & Tanaka, 1978) or neomycin (Potter, Matthews el ai, 1965) binding activity. An intermediate approach was to study the binding of gentamicin to subcellular fractions of noninfected organs or tissues (Kunin, 1970;Komguth, Bayer & Kunin, 1980). The clinical relevance of these studies is as yet uncertain, because most of the results on gentamicin binding have been obtained under somewhat unphysiological conditions: either the gentamicin binding assays were performed in salt buffers of too low an ionic strength (Bryant & Hammond, 1974;Kornguth et ai, 1980), or the binding was assessed after the purulent samples had been strongly homogenized (Bryant & Hammond, 1974;Davis & Bruns, 1978).…”

Gentamicin Inactivation in Purulent Exudates: Role of Cell Lysis

“…Antimicrobial agents are known to bind to, and to be partially and reversibly inhibited by, a variety of tissue constituents, including interstitial fluid proteins, cell membranes, soluble intracellular proteins, and particulate intracellular components [1][2][3]. Thus, such sedimentable components have been shown to bind avidly gentamicin and polymyxin in purulent exudates, leading to a considerable reduction of the concentration of the free, biologically active drugs [4].…”