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Twenty patients with peripheral arterial disease and 10 normal controls were submitted to i.v. injection of aprotinin, polypeptide (mol.wt. 6512) extracted from bovine lung, in order to examine its effects on: (a) lower limbs pain, (b) lower limbs sensibility, (c) calf blood flow. Aprotinin (100,000 Ku i.v. diluted in NaCl 0.9%) was given in a single dose or twice a day for a week; for control the same subject received, before or after aprotinin, an equivalent volume of diluent (0.9% NaCl). The results demonstrate that aprotinin is able to increase the initial pain limit walking tolerance and to decrease the intensity of pain at rest and of myalgic or "trigger" areas. No variation was observed on skin sensibility and on calf blood flow, both basal resting and hyperemic. The favorable effect of examined polypeptide on ischemic pain can be attributed neither to increase of calf blood flow nor to influence on perception of painful stimuli. It seems therefore to suggest that aprotinin acts on biochemical mechanisms that cause the ischemic pain. Presumably it inhibits kininogenases and tissue protein-hydrolyzine enzymes activated in the course of ischemia.

The morphological changes in striated muscle following ischemia has been so far mainly studied with both optical and electron microscopes taking into consideration different parameters, such as duration, nature and course of the ischemia. 1, ~~ 3 The study of the metabolic changes in the above lesions was approached by measuring the lactate-pyruvate ratio, ATP, inorganic phosphorus, lactic acid and glycogen contents.4 Then a series of studies was reported on the alteration of metabolism in infarcted heart muscle following experimental occlusion of coronary vessels in dogs. The results of these studies have demonstrated that the first step in the reparative process is an enhancement in the synthesis of nuclear material associated with a marked increase in activity of the pentose phosphate shunt, and a sharp decrease in activity of mitochondrial (respiratory) and glycolytic enzymes.5Interest in the latter prompted our investigation on protein synthesis, oxygen uptake and anaerobic glycolysis in skeletal muscle following incomplete and &dquo;less&dquo; incomplete ischemia in rats as well as in rabbits. We reported elsewhere the results obtained using sural muscles ischemized incompletely by exclusion of the femoral and external iliac arteries. These results were consistent with an enhancement of C14-leucine incorporation into protein associated with an increase in activity in both oxygen and anaerobic glycolysis. The experimental conditions of incomplete ischemia were adopted to reproduce the main pathological features in human skeletal muscle following chronic vascular diseases.The results of the study on rabbit sural muscle ischemized at a &dquo;less&dquo; incomplete stage are reported in this present paper. We studied the metabolic responses to such an ischemia in relation to the pentose phosphate shunt, to glycolysis and respiration and measured the activity of eight main enzymes. Furthermore we checked the endoergonic processes by incorporating C14-leucine into protein. These data are in general agreement with those reported in infarcted heart muscle. MATERIALS AND METHODS Animals and surgeryExperiments were carried out on 16 young rabbits of both sexes, weighing around 2,500 gm, under local anaesthesia by subcutaneous injection of 1% novocaine. The femoral artery was excluded by ligature with a silk thread and at University of Otago Library on March 15, 2015 ang.sagepub.com Downloaded from