Small-animal intubation is often necessary during inhalation anesthesia to allow steady-state conditions for large operations and in vivo experiments in all fields of experimental surgery. In rats, placing an orotracheal tube is technically difficult primarily because of the small size of the subject and the lack of equipment specifically designed for this task. We describe a simple rat intubation technique in which the animal is suspended in dorsal recumbency on an inclined metal plate. The animal, anesthetized with ether, is fixed to a 70 degrees-inclined metal plate in a dorsal position by means of a Mersilene ribbon hooked around the upper incisors. This method of positioning the animal is the most important step in the intubation process and further facilitates the technique already described by other authors. A human otoscope was used as a laryngoscope, intubation was performed using the Seldinger technique, and a 14-gauge intravenous catheter served as an endotracheal tube. This inexpensive technique is quickly learned and can be used in any laboratory. Safe and reliable airway management can thus be achieved, permitting in vivo examinations and operations.

No abstract

No abstract

No abstract

No abstract

1) In the Tx rat lower incremental plasma glucose after oral glucose intake likely results from decreased intestinal glucose uptake; 2) preservation of a normal entero-insular axis of insulin together with the absence of intestinal malabsorption of lipids suggest that orthotopic transplantation of a duodeno-pancreas preserved endocrine and exocrine pancreatic function and therefore qualifies as treatment modality for the above named indications.

Heterotopic pancreas transplantation in type I diabetic patients does not correct hyperglucagonemia, which is thought to be due to insufficiently suppressed glucagon release by the host pancreas. The diabetogenic effects of glucagon then have to be corrected by higher than normal insulin secretion from the transplant, with the attendant risk of earlier loss of islet cell function, and development of atherosclerosis. To establish whether this situation can be prevented, we investigated glucose homeostasis and blood lipids, as well as fecal fat and chymotrypsin as indicators for pancreatic exocrine function 14 weeks after orthotopic pancreas transplantation in inbred rats. The pancreas was resected before orthotopic transplantation of the donor pancreas with portal venous drainage (n=8). Laparotomized animals served as controls (n=8). Basal plasma glucagon, basal plasma insulin to glucagon molar ratio, and basal and integrated incremental responses of plasma glucose, insulin, and C-peptide after an oral glucose load (2 g/kg body weight) were similar in both groups. However, hepatic insulin clearance was slightly but significantly lower in the transplanted group (1.1+/- 0.1 vs 1.6+/-0.2; P<0.05). Basal plasma levels of free fatty acids, phospholipids, triglycerides, cholesterol, low-density lipoproteins, and high-density lipoproteins were unchanged after transplantation. Also unchanged were fecal fat and chymotrypsin levels, thus indicating preserved pancreatic exocrine function. We concluded that orthotopic pancreas transplantation with portal venous drainage achieves almost optimal metabolic control with respect to endocrine and exocrine pancreatic function as well as blood lipids. This technique could therefore be used to treat combined endocrine and exocrine insufficiency in chronic pancreatitis and thus enlarges the spectrum of indications for pancreas transplantation.

Primary disturbances in mineral metabolism and deficiencies in insulin and insulin-like growth factor-I (IGF-I) have been implicated in the pathogenesis of diabetic osteopenia. This prompted us to investigate whether normal bone minerals and bone morphology are preserved after pancreas transplantation. To this end, 8 inbred rats (transplants) were compared with 9 sham-operated rats (controls) 20 months after orthotopic pancreas transplantation. While basal levels of insulin remained unaffected by transplantation, an oral glucose load elicited hyperinsulinemia (integrated incremental response: mean +/- SEM, 62+/-8 nmol l(-1) 60 min in transplants vs. 32+/-6 nmol l(-1) 60 min in controls; p<0.01) in the presence of normal glucose levels. Fecal and urinary excretion and fractional intestinal absorption of calcium, magnesium and phosphorus, net calcium absorption and the respective serum mineral levels were unchanged after transplantation, as were those of the calciotropic hormones. Serum osteocalcin and bone alkaline phosphatase remained unaffected, and urinary excretion of pyridinium and deoxypyridinium were unchanged. Fasting plasma IGF-I concentration was significantly decreased in transplants (930+/-42 ng ml(-1)) vs. control rats (1074+/-49 ng ml(-1); p < 0.05). Despite similar physical and chemical properties of bone in both groups, histomorphometry revealed slight osteopenia in transplant rats, as reflected by a 38% reduction in the cancellous bone area of the proximal tibial metaphysis. Plasma IGF-I levels were significantly correlated with bone mineral apposition rate (r=0.70, p<0.02), osteoblast perimeter (r=0.60, p<0.05) and osteoid perimeter (r=0.60, p<0.05). In conclusion, pancreas transplantation preserves physical and chemical properties of bone, but bone metabolism is not completely normal after transplantation, as evidenced by decreased cancellous bone. This might have resulted from the insulin resistance associated with the lowering of the plasma IGF-I level, which was correlated with the mineral apposition rate.