RESUMEN
PURPOSE: We examined preoperative glucose administration to establish what dose and cutoff point were optimal for suppression of lipolysis and prevention of hypo- or hyperglycemia. METHODS: Rabbits were preoperatively fasted and simultaneously received glucose at a constant rate of 0, 0.1, 0.2, 0.3, or 0.4 g.kg(-1).h(-1) in fluid infusion for 3 h. Plasma glucose, immunoreactive insulin activity, nonesterified fatty acids, and ketone bodies were measured 0, 1.5, 3 and 4 h after the start of infusion, and hepatic glycogen content was assessed 1 h after cessation of infusion. RESULTS: Fluid infusion without glucose decreased plasma glucose. Glucose administration at more than 0.2 g.kg(-1).h(-1) caused hyperglycemia (>200 mg.dl(-1)) in the infusion period; the differences were significant compared with the value at zero time or in the 0 g.kg(-1).h(-1) group (P < 0.01). The highest dose also raised plasma immunoreactive insulin activity, which was significantly higher than in the 0 g.kg(-1).h(-1) group (P < 0.01) at the midpoint of the infusion period. Plasma nonesterified fatty acids increased in all groups. The changes were, however, significantly reduced in both the 0.3 and 0.4 g.kg(-1).h(-1) groups (P < 0.05 and P < 0.01, respectively) by the end of infusion. All these effects of glucose supply, including suppression of lipolysis, disappeared regardless of dose within 1 h after the cessation of infusion. CONCLUSION: These results suggest that the optimal dose for preoperative glucose infusion, in order to preserve carbohydrate or fat metabolism, is 0.1-0.2 or 0.3 g.kg(-1).h(-1), respectively, and indicate that administration should not be discontinued until the start of surgery.
RESUMEN
We analyzed and compared the physicochemical and immunochemical properties of recombinant human serum albumin (rHSA) from Pichia pastoris with those of plasma-derived human serum albumin (pHSA). The second virial coefficient of rHSA, obtained from colloid osmotic pressure measurements at pH 6.7 +/- 0.1 was not significantly different from that of pHSA (P > 0.05). A 25% rHSA solution exhibited Newtonian flow, and the viscosity of 25% rHSA at 20 +/- 0.02 degrees C was not significantly different from that of 25% pHSA (P > 0.05). We analyzed the long- and medium-chain fatty acid composition of rHSA by reverse-phase HPLC using 9-anthryldiazomethane as the fluorescent labeling reagent. The total amount of fatty acid was higher for pHSA than for rHSA. The fatty acid composition of the rHSA preparation was the same as that of the pHSA preparation. However, the amounts of palmitic acid (C16:0) and stearic acid (C18:0) in rHSA were much lower than those in pHSA. Interestingly, we found that P. pastoris produced linolenic acid (C18:3) because it was detected in rHSA. The immunochemical properties of rHSA were analyzed by a parallel line assay method using anti-pHSA polyclonal antibody, and were identical to those of pHSA (P > 0.05).
Asunto(s)
Pichia/genética , Albúmina Sérica/química , Albúmina Sérica/genética , Secuencia de Aminoácidos , Animales , Antígenos/química , Antígenos/genética , Fenómenos Químicos , Química Física , Reacciones Cruzadas , Ácidos Grasos/análisis , Humanos , Inmunoquímica , Oligopéptidos/química , Oligopéptidos/genética , Oligopéptidos/inmunología , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Seguridad , Albúmina Sérica/inmunologíaRESUMEN
In order to investigate the optimal fat content for total parenteral nutrition (TPN) solutions, male Wistar rats were subjected to 70% hepatectomy and then placed, for five days, on one of five TPN regimens in which fat represented 0%, 10%, 20%, 30% and 40%, respectively, of the total calorie content. As serum triglyceride levels in the fat-treated groups were lower than those in the non-treated normal rats, it was concluded that the administered fat was sufficiently hydrolyzed. The greater the fat content, the higher the regeneration rate of the remnant liver. Significant differences were found between the 0%-fat group and 20%-plus fat groups. Hepatic triglyceride level was significantly lower in the 20%-fat group. Hepatic protein level was significantly elevated in all fat-treated groups. Serum phospholipids and total cholesterol due to the lecithin contained in fat emulsion were significantly elevated in the 30 and 40%-fat groups, indicating that fat content of 30 and 40% was excessive. The results suggest that TPN containing fat is superior to fat-free TPN for liver regeneration after partial hepatectomy, and that optimal fat content is estimated to be about 20% of total calorie content in the case of this fat emulsion.
Asunto(s)
Grasas de la Dieta/administración & dosificación , Hepatectomía , Nutrición Parenteral Total , Animales , Peso Corporal , Grasas de la Dieta/análisis , Lípidos/sangre , Hígado/metabolismo , Hígado/fisiología , Hígado/cirugía , Regeneración Hepática , Masculino , Tamaño de los Órganos , Ratas , Ratas Wistar , UrinálisisRESUMEN
Urea formation, cell number, cellular protein content and tyrosine transaminase activity were not changed by PCB addition in cultured rat hepatocytes. These results indicate that these liver functions are similar to control levels despite the addition of PCBs. Our results show that primary cultured hepatocytes mimic partially the intact liver in relation to some responses to PCBs. In isolated hepatocytes as well as in vivo, PCBs increased in cellular ascorbic acid level, aryl hydrocarbon hydroxylase and UDP-glucuronyl transferase activities. Thus, the present results may suggest that the metabolic changes in vivo concerning ascorbic acid induced by dietary PCBs were primarily related to the direct effects of PCBs per se on liver parenchymal cells.