New Releases by David Lucas

Halibut Jackson doesn''t like to be noticed and makes sure that he always blends into the background. But when he is invited to the palace, he makes a mistake and everyone notices him.

Bored with her meals of cardboard, string, and sawdust, Nutmeg acquires from a genie a magic spoon to make some different dishes but winds up with more than she bargained for.

The landmark Supreme Court property rights decision by the man who won it. A truly significant event in the defense of property rights, told informatively and entertainingly.

The aim of this project was to develop suitable experimental animal models of the cardiovascular complications which frequently occur in the human diabetic. Such models are required in order that possible causes and forms of therapy may be more thoroughly investigated than is possible in human diabetics. Several metabolic parameters were measured in rats with experimental diabetes resulting from alloxan or streptozotocin administration and from pancreatectomy in order to determine the form and severity of each. It was decided to measure several cardio-vascular parameters in two of these groups namely alloxan and streptozotocin diabetic. A group of genetically obese rats were also included in this study. Both diabetic groups when pithed were found to have reduced pulse pressure and heart rate responses to catecholamines and acetylcholine. Resting pulse pressure was increased and heart rate decreased. Isolated atria from similarly diabetic rats had correspondingly lower rates and greater forces of contraction and a reduced sensitivity to catecholamines, this sensitivity being further reduced when the media glucose concentration was raised. Genetic obesity appeared to have no effect on the above parameters. The reduced pressor response to noradrenaline found in the pithed diabetic rate contrasted with previous results, this contrast suggesting that sensitivity changes in the cardio-vascular systems of the diabetic rat are uneven and that this would lead to a redistribution of blood flow away from the extremities in favour of other areas. This was confirmed by blood flow studies using a radioactively labelled microsphere technique. Since circulatory insufficiency of the extremities is a characteristic complication of human diabetes such blood flow studies in the diabetic rat may provide a suitable model of these complications. Possible metabolic and hormonal causes of the changes seen in both rats and man and areas for further investigation including a possible therapeutic approach are discussed.