Repeated pregnancy without lactation: effects on maternal glycemic control, pregnancy outcome, carcass composition, and fat distribution in rats

Repeated pregnancy without lactation in rats has been reported to produce permanently elevated carcass fat mass and hyperplasia in subcutaneous fat depot. In the present study, the pregnancy outcome, intravenous glucose tolerance ability (IVGTT), and carcass composition were further examined in Osborne-Mendel rats. Female rats were divided into pregnancy-lactation (PL), pregnancy-no lactation (PNL), and control (CON) groups. Half of the rats were killed after three pregnancy/lactation cycles, whereas the rest were given a 12-week rest period before killing. It was found that rats in PNL group had fasting hyperglycemia and insulin insensitivity during the third pregnancy (P less than or equal to .05), elevated spontaneous abortion rate (P less than or equal to .05), and elevated subcutaneous fat content (P less than or equal to .01) relative to that of PL rats or CON rats. After a 12-week rest period, a significant increase in subcutaneous fat cell number was also observed in PNL rats. PL rats, on the other hand, have significantly elevated internal/subcutaneous fat ratios (P less than or equal to .05), both immediately after weaning and after the 12-week rest period. The significance of this change is not yet known.

Role of interleukin 1 and tumor necrosis factor on energy metabolism in rabbits

A study of the combined effects of intravenous infusion of the recombinant cytokines beta-interleukin 1 (IL-1) and alpha-tumor necrosis factor (TNF) on energy substrate metabolism in awake, conditioned, adult rabbits was performed. After a 2-h basal or control period, 48-h fasted rabbits were administered TNF and IL-1 as a bolus (5 micrograms/kg) followed by a continuous intravenous infusion (25 ng.kg-1.min-1) for 3 h. Significant increases in plasma lactate (P less than 0.01), glucose (P less than 0.01), and triglycerides (P less than 0.05) occurred during the combined infusion of IL-1 and TNF, whereas neither cytokine alone had no effect. There was a 33% increase in the rate of glucose appearance (P less than 0.05), but glucose clearance was not altered compared with the control period. Glucose oxidation increased during the combined cytokine infusion period and glucose recycling increased by 600% (P less than 0.002). Lactic acidosis and decreased oxygen consumption, as a result of the cytokine infusions, indicated development of anaerobic glycolytic metabolism. A reduction in the activity state of hepatic mitochondrial pyruvate dehydrogenase (65 vs. 82% in control animals, P less than 0.05) was consistent with the observed increase in anaerobic glycolysis. Thus the combined infusion of IL-1 and TNF in rabbits produces metabolic manifestations seen in severe injury and sepsis in human patients and, as such, may account for the profound alterations of energy metabolism seen in these conditions.

Anatomical analysis of the cause of skin necrosis of the great toe after transplantation of the great toe nail flap

Necrosis of skin on the medial side of the great toe has been a significant complication of the great toe nail flap. To investigate the reason for this, a study of the blood supply of the medial side of the great toe was carried out on 55 feet with the injection of red latex into the arteries and on 13 vascular cast specimens. It was found that, after the blood vessels from the plantar and dorsal sides of the great toe are severed during the operation, the skin of the medial side of the great toe is mainly supplied by the medial vascular network at the head of the first metatarsal bone. It is clear that the blood supply from this network may sometimes be insufficient to nourish the skin. It is suggested that the operative incision should be changed so as to increase the blood supply to the medial vascular network which may decrease the incidence of skin necrosis.

Vallesiachotamine and isovallesiachotamine from the seeds of Strychnos tricalysioides

The alkaloids vallesiachotamine and isovallesiachotamine have been isolated from the seeds of Strychnos tricalysioides and identified on the basis of their spectral characteristics. The potential chemotaxonomic significance of these alkaloids is briefly discussed.