Effect of granulocyte colony stimulating factor on pig blood platelets treated with cisplatin in vitro.

The effects of granulocyte colony stimulating factor (G-CSF) and cisplatin in vitro on the peroxidation of pig platelet endogenous arachidonate were investigated. Estimation of the level of malonyldialdehyde (MDA) after stimulation of platelets with thrombin served as an indicator of this process. MDA concentration was determined by means of a modified method with thiobarbituric acid. The effects of G-CSF on thrombin-induced formation of MDA in platelets was dependent on the concentration and the time of platelet preincubation with this cytokine. In the platelets obtained from the whole blood preincubated with the highest concentration of G-CSF (8 microg/ml), a significant increase of MDA formation was observed (p<0.01). Cisplatin (20 microM) had a strong inhibitory effect on arachidonic acid metabolism in platelets (p<0.001). In the presence of G-CSF (0.8 microg/ml) in incubation medium the inhibitory effect of cisplatin on platelet arachidonate pathway was reduced. The results showed that G-CSF had a protective effect against cisplatin action on platelets.

Concentration of 2,3-diphosphoglycerate and adenosine triphosphate in erythrocytes following acute blood loss in the beagle.

The effect of experimental anaemia induced by phlebotomy and the effect of infusion of various fluids on the 2,3-DPG, ATP and total organic phosphate (Porg) concentration were examined in the red cells of beagles made anaemic by withdrawal of 30% of the circulating blood. Particular groups of dogs 30 min after phlebotomy were infused with own blood, blood with inosine, pyruvate and phosphate (IPP), Fluigel and Fluigel with IPP. The changes were most distinct in dogs which were not infused with any fluid. After 24 hours the content of 2,3-DPG, ATP and Porg increased by 17, 27 and 20%, respectively, in comparison with the results obtained before blood loss. Twenty-four hours following the reinfusion of own blood, a slight increase occurred in the 2,3-DPG and Porg content. Infusion of Fluigel caused a decrease of the phosphate compounds concentration after 3 and 6 hours and then the concentration almost returned to normal. Infusion of own blood as well as Fluigel enriched with inosine, pyruvate and phosphate did not lead to any change in 2,3-DPG concentration. The red cells of dogs do not utilize inosine for 2,3-DPG or nucleotide synthesis. The increased cardiac output seems to the main mechanism for oxygen transport to tissues after an acute haemorrhage.