Effect of antiarrhythmic drugs on the postischaemic metabolic recovery of isolated rat hearts.

In isolated perfused rat hearts, global ischaemia for 20 or 40 min led to a substantial decrease of myocardial ATP, creatine phosphate and glycogen, and to an increase in lactate and glucose-6-phosphate. Subsequent coronary reperfusion was associated with severe tachyarrhythmias (ventricular fibrillation occurring in 40% of the hearts after 20 min of ischaemia, and in 100% after 40 min of ischaemia) and the release of great activities of creatine kinase. Metabolic recovery was obtained only in hearts in which reperfusion-induced fibrillation was lacking. Significant improvement of the metabolic recovery during reperfusion was obtained with corynanthine, a stereoisomer of yohimbine, given in concentrations which prevented reperfusion-induced fibrillation. Moreover, a highly significant decrease of the enzyme release was observed. Similar results were obtained with quinidine. Lidocaine (30 mumol/l) failed to prevent ventricular fibrillation and had no beneficial effect on myocardial metabolism. The effects of these antiarrhythmic drugs are discussed in view of the importance of ventricular fibrillation on postischaemic metabolic recovery.

Fc receptors mediate prostaglandin and superoxide synthesis in cultured rat Kupffer cells.

Latex beads with covalently bound bovine serum albumin were prepared and coated with anti-BSA immunoglobulin G. These particles were shown to possess on their surfaces a defined quantity of the antibody with the Fc portions exposed to the medium. One homologous and two heterologous antibodies of the G class were used and compared in terms of their binding to the rat Kupffer cells and their ability to elicit the typical phagocytotic responses. These particles were phagocytosed by rat Kupffer cells and elicited synthesis of prostaglandins and superoxide anion radicals. A significant release of superoxide into the medium was observed in the presence of cytochalasin B only. The data presented here suggest that a) Fc-carrying particles can be bound to Kupffer cells and elicit responses via specific receptors; b) coating with the homologous antibody yields the most effective particles; c) superoxide release into the surrounding medium is most abundant when the particle-binding membrane areas are prevented from forming phagocytotic vesicles.

[Ambulatory sonography in clinical and general practice. Incidence and accuracy of findings and consequences]. / Ambulante Sonographie in Klinik und Praxis. Häufigkeit und Sicherheit von Befunden und deren Konsequenzen.

In a prospective study an ultrasound examination was performed in 372 out-patients. 230 were examined in two physicians offices (group I) and 142 in a clinical ultrasound center (group II). The indication for ultrasound was different in both groups: 42% of patients in group I were examined without exact questions. Search for primary tumors or metastasis were more often indications in group II. More patients were found to have liver abnormalities and less biliary disease in group II. The impact of ultrasound findings on final diagnosis was not different. More diagnostic and therapeutic consequences resulted in group I, in particular in patients with cholelithiasis. A broad indication for sonography in the physicians office is justified given sufficient experience of the examiner. With respect to the consequences of the findings improvement is warranted.