No abstract

Patency of vein grafts may be influenced by the medium in which they are stored temporarily. We compared saline solution vs blood on prostanoid production and maintenance of endothelium in canine veins after 1 hour of storage at 23 degrees C with 0.2 mg/ml of papaverine. Spontaneous and arachidonate-stimulated prostaglandin levels were measured by radioimmunoassay. Endothelial integrity was analyzed by light and electron microscopy. Prostaglandin production in blood vs that in saline solution was 1821 +/- 1264 and 1259 +/- 719 pg/cm2/min at control and 6705 +/- 3702 vs 6264 +/- 3409 pg/cm2/min, respectively, after stimulation. There were no statistically significant differences between the groups at any time point. Thromboxane levels were also indistinguishable between groups. Microscopy revealed 70% endothelial loss in blood vs 95% for saline solution. We conclude that endothelial preservation is enhanced by blood storage, that the medial layer produces substantial amounts of prostacyclin, and that additional storage solutions need to be investigated.

Effects of i.v. infusion of urea were studied in 26 cats by recording spontaneous cortical activity and somatic afferent evoked potentials from the posteroventral lateral nucleus of the thalamus and periaqueductal midbrain reticular formation. Subsequent to the administration of a 20% solution of urea, spindling and seizure discharges appeared in the electrocorticogram. The evoked potentials from the posteroventral lateral nucleus of the thalamus and reticular formation remained unchanged. Control studies indicated that the operative procedure, including the insertion of subcortical electrodes, hydration incident to fluid administration, possible deterioration of the preparation and alteration of the osmolarity of the serum did not produce the observed results. It was demonstrated that urea administered intravenously, in amounts producing blood NPN values commensurate with those observed in patients with uremia, alters cortical activity and excitability.

Patency of vein grafts may be influenced by the medium in which they are stored temporarily. We compared saline solution vs blood on prostanoid production and maintenance of endothelium in canine veins after 1 hour of storage at 23 degrees C with 0.2 mg/ml of papaverine. Spontaneous and arachidonate-stimulated prostaglandin levels were measured by radioimmunoassay. Endothelial integrity was analyzed by light and electron microscopy. Prostaglandin production in blood vs that in saline solution was 1821 +/- 1264 and 1259 +/- 719 pg/cm2/min at control and 6705 +/- 3702 vs 6264 +/- 3409 pg/cm2/min, respectively, after stimulation. There were no statistically significant differences between the groups at any time point. Thromboxane levels were also indistinguishable between groups. Microscopy revealed 70% endothelial loss in blood vs 95% for saline solution. We conclude that endothelial preservation is enhanced by blood storage, that the medial layer produces substantial amounts of prostacyclin, and that additional storage solutions need to be investigated.