The usefulness of a new voltage-sensitive fluorescent dye, the membrane permeant negatively charged oxonol dye diBA-C4-(3)-, was evaluated by measuring the membrane potentials of BICR/M1R-k and L cells with glass microelectrodes and simultaneously recording the fluorescence of the stained cells. The membrane potential of BICR/M1R-k cells was varied between -25 mV and -90 mV by changing the bicarbonate concentration in the medium or by voltage clamping. To avoid any interference by the inserted electrodes with the fluorescence measurement of the cytoplasm, the cells were fused by polyethyleneglycol to form giant cells (homokaryons). These homokaryons also allowed penetration by two glass microelectrodes without causing a serious leakage of the plasma membrane. The slow responding dye diBA-C4-(3 )-had a fluorescence response of about 1% per mV. Mathematical analysis of the fluorescence changes after voltage clamping revealed a first-order reaction with a rate constant between 0.1 min-i and 0.8 min-i, depending on the cell size which was determined by the number of nuclei per homokaryon. A model for the mechanism of the fluorescence changes is proposed.

Abstract--Ll210 mouse leukemia cells have been exposed to different doses of shock waves generated by underwater spark discharge at 18 kV in an experimental lithotripter (XL1, Dornier). Histological and flow cytometric investigations revealed severe damage and a LDso of about 420 shock waves when the cells were treated as suspensions. Cells immobilized in gelatine, however, were unaffected, indicating that secondary effects are responsible for the cellular damage. Possible mechanisms such as cavitation, jets, and shear forces are discussed.

Summary.Extracorporeal shock wave lithotripsy has become established worldwide as the method of choice for the treatment of nephrolithiasis and ureterolithiasis over the last 10 years. Although initial studies showed no damaging effects of the shock waves on organs and tissues, numerous recent reports have presented evidence for severe acute effects and chronic complications after shock wave treatment. The pathophysiological effects on kidneys and the histopathological effects on organs or tissues in man and animal, and also the effects on ceils in culture and tumors are sumarized. Suspended and immobilized cell cultures were used to characterize and quantify the efficacy of shock wave. Extended applications of shock waves and possible modifications to shock wave generators are discussed.A reproducible generation of shock waves in fluids was first reported by Eisenmenger [31,32], who described an electromagnetic arrangement using a flat solenoid and a metal membrane. About 20 years later, underwater sparkgap-induced shock waves were used for kidney stone disintegration [17], a procedure that has become clinical routine [30]. In the meantime, the third generation of lithotripters has been developed (Siemens Lithostar Plus, Dornier Compact, Storz Modulith). Most of them are equipped with electromagnetic shock-wave emitters (EMSE), but piezo-electric shock-wave sources (Piezolith 2500, Diasonics) with similar properties for stone fragmentation are also in clinical use. However, all commercially available shock-wave generators (spark gap, electromagnetic, piezo-electric) produce side effects that accompany stone disintegration in patients. Furthermore, their biological effects are described as injuries to organs or tissues in vivo that have been exposed to the focal area of shock waves and as damage to cells in culture that have been treated with shock waves. * Dedicated to Prof. Dr. Wolfgang Eisenmenger on the occasion of his 60th birthday Side effectsIn kidney-or gallstone treatment with shock waves, side effects are equivocally classified and certainly depend not only on the number and energy of the applied shock waves but also on the disposition of the patients. Petechial bleeding of the skin that can be observed macroscopically has been found in about 10% of patients [29]. Varying degrees of subcapsular fluid collection and hemorrhage have been detected using different methods [4,37,71].Most of the damage typically caused by shock-wave treatments is routinely observed and is not considered to represent severe pathological change, but the occurrence of perirenal hematoma has increased significantly in patients with pre-existing or poorly controllable hypertension [47]. Physiological tests have revealed only minor, transient reductions of renal plasma flow in the treated kidney [45,82] and no clinically relevant changes in blood chemistry [17]. Furthermore, cytoplasmic enzymes have been reported to be only transiently released into the blood and urine of shock-wave-treated patients [46]. Kishimoto et al. [46] ha...

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