Our data suggest that changes in the AMPAR isoforms could be associated with ageing in the different structures studied. Although GluR2 editing seems to be involved in age-dependent vulnerability to ischaemia supporting the 'GluR2 hypothesis', this alone does not explain the differential vulnerability in the different brain regions. Finally, inflammation could play a role in protection from I/R-induced injury.

We describe a simple and feasible procedure for performing intravenous administration of substances in the gerbil. Under light anaesthesia, animals were held in dorsal recumbency and a very small incision of skin, parallel to the femoral vein on the internal side of the thigh, was made. The vein is easily accessible via thin skin incision. An insulin syringe and a 30 G needle were used for the injection. This is an easy and quick method, which, with appropriate anaesthesia, allows rapid recovery.

A case of right renal agenesis in a beagle, of interest because of the age of the dog at the time of diagnosis, is described. Physical, haematological, biochemical and urinary examinations, including measurement of endogenous creatinine clearance, were performed to assess renal function. Survey radiography, excretory urography, ultrasonography, computed tomography and nuclear magnetic resonance examinations were also used to confirm the absence of a kidney. The effect of kidney agenesis on renal function, evaluated on the basis of endogenous creatinine clearance, is discussed together with the benefits of the various imaging techniques to enable in vivo detection of renal abnormalities.

-Twenty-four hour urinary excretion, fractional excretion and the filtered load of calcium and phosphorus were monitored as hyperparathyroidism evolved in a model of progressive canine renal failure. Thirteen beagles of both sexes aged four and a half months were used. Nine of them were subjected to a renal damaging schedule (neomycine, 60 mg/kg/48 h, IM, 32 weeks) in order to induce chronic renal failure leading to secondary hyperparathyroidism (2HPT group). The remaining four were kept as the control group. The experiment was conducted over 32 weeks. Blood and 24 h urine were collected every four weeks. Calcium, phosphorus and creatinine were analyzed. Plasma parathormone and calcitonin were determined at weeks 0, 12, 24 and 32. The level of renal function in the 2HPT animals was reduced to 25% of that of the controls (endogenous creatinine clearance was 0.45 ± 0.22 mL/min/kg as opposed to 1.81 ± 0.54 mL/min/kg). Hyperparathyroidism was confirmed by a progressive increase in the levels of the parathyroid hormone. Calcitonin levels were not modified. A tendency to hypocalcaemia was observed, reaching statistically significant levels from the twenty-eighth week of the study, when hyperphosphataemia also became significant. Daily urinary excretion of calcium and phosphorus remained at values considered normal throughout the experiment with no alteration imputable to the impaired renal function. This is explained by the decrease in the filtered load of these elements (in both cases statistically significant from the 24th week on) being associated with an increase in their fractional excretion. Thus, calcium and phosphorus urinary excretion values could be maintained in a normal range up to the end of the experiment, showing that renal calcium handling in dogs with experimentally induced renal failure seems to differ from that observed in human patients. renal hyperparathyroidism / calciuria / phosphaturia / parathyroid hormone / calcitonin / dog