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Age dependence of platelet reactivity
ABSTRACTS OF 12TH INTNAT’L CONGRESS
Vol. 65, SuppI. 1
P278 AGE DEPENDENCE OF PLATELET REACTIVlTY M. PaHzek, M. Penka Dept. Clin. Chem., Gen. Hosp., Nov); Jicin and 2nd Dept. Med., Masaryk University, Bmo, CS Within the scope of the care scheme for aged and long time sick persons the authors examined 413 patients without any clinical manifestation of cardiovasculan metabolic or malignant diseases, the age span being 20-92 years. At the same time 28 patients were examined with diabetes mellitus, 29 patients with angina pectoris, 25 persons with hyperlipoproteinemia Ha and IJb and 25 persons with myocardial infarction. Beside the age dependence of some biochemical and hematological parameters the authors point out to significant changes in hemostasis manifested by the increased reactivity of thromboqtes. Within the age groups 65-75 and those above 75 years the patological changes have been observed approaching those found in patients with HLP, DM and AMI. An aggregation response to low ADP and adrenaline concentrations was also noted. Moreover, the increased amount of circulating aggregates, increased concentration of beta thromboglobulin, tibrinopeptide A and increased formation of TXB, from exo@nous arachidonic acid was observed. On the other hand, only statistically nonsignificant changes were found in the case of F VIII-RA,, protein C and platelet protein spectrum. In spite of certain problems connected with the standardisation of laboratory tests the authors feel that it is possible to create a set of diagnostic methods suitable for the follow-up of the risk group of population. This might become a basis for introduction of efficient dietetic or prophylactic treatment.
P279 EPIDERMAL GROWTH FACTOR (EGF) AND PLATELET FUNCTlGN BEFORE AND AFTER EXERCISE A. Bodzenta-Lukaszyk, A. Lukaszykl, A. Gabryelewiczl, S. Konturek?, M. Bielawiec Departments of Haematology and I Gastroenterology, Academy of Medicine, Bialystok PL, and 1 Institute of Physiology, Academy of Medicine, Krakow, PL EGF has been found to be associated with blood platelets. It has been also found that the concentrations of salivary, plasma and urinary EGF were increased after prolonged submaximal exercise, when both alpha- and betaadrenergic systems are activated. However, little is known about the role of EGF in platelet function. Therefore, the purpose of this study was to determine, whether serum or plasma EGF released aRer exercise affects bIood platelet function. Six healthy male volunteers, were submitted to a submaximal bicycle ergometry test. Blood for platelet function studies and determination of EGF concentrations was taken via the intravenous cathteter before starting exercise and after 15.30 and 60 minutes rest. A similar scheme was followed to investigate changes in the same parameters induced by a slow intravenous infusion of 0.3 mg/kg b.w. phentolamine (PHEN). Re.sults: The platelet count dropped significantly 30 min after exercise whereas I5 and 60 min after exercise there were no significant changes in platelet count. Following exercise the platelet count was never influenced by administration of PHEN. While evident increase of ADP and adrenaline (ADR) induced platelet aggregation (15 and 30 and 60 min after exercise) was noticed, the platelet aggregation induced by arachidonic acid (AA) and PAF was almost unchanged. Infusion of PHEN markedly increased the TAC of ADR only in the aggregation test. There were no significant changes in plasma TXB, level 15 and 30 min after exercise while 60 min after of little increase in TXB, level was noted. PHEN infusion does not affect plasma level of TXB, after exercise. EGF concentrations in serum and plasma were raised 15 min after exercise. Infusion of PHEN markedly increased the EGF concentrations in serum and plasma ( I5 and 30 min after exercise). These results show that exercise causes a fall in platelet count accompanied by the increase in ADP- and ADR-induced platelet aggregability and the increment in plasma EGF suggesting a close interaction between EGF and platelet function.
Vol. 65, SuppI. 1
P278 AGE DEPENDENCE OF PLATELET REACTIVlTY M. PaHzek, M. Penka Dept. Clin. Chem., Gen. Hosp., Nov); Jicin and 2nd Dept. Med., Masaryk University, Bmo, CS Within the scope of the care scheme for aged and long time sick persons the authors examined 413 patients without any clinical manifestation of cardiovasculan metabolic or malignant diseases, the age span being 20-92 years. At the same time 28 patients were examined with diabetes mellitus, 29 patients with angina pectoris, 25 persons with hyperlipoproteinemia Ha and IJb and 25 persons with myocardial infarction. Beside the age dependence of some biochemical and hematological parameters the authors point out to significant changes in hemostasis manifested by the increased reactivity of thromboqtes. Within the age groups 65-75 and those above 75 years the patological changes have been observed approaching those found in patients with HLP, DM and AMI. An aggregation response to low ADP and adrenaline concentrations was also noted. Moreover, the increased amount of circulating aggregates, increased concentration of beta thromboglobulin, tibrinopeptide A and increased formation of TXB, from exo@nous arachidonic acid was observed. On the other hand, only statistically nonsignificant changes were found in the case of F VIII-RA,, protein C and platelet protein spectrum. In spite of certain problems connected with the standardisation of laboratory tests the authors feel that it is possible to create a set of diagnostic methods suitable for the follow-up of the risk group of population. This might become a basis for introduction of efficient dietetic or prophylactic treatment.
P279 EPIDERMAL GROWTH FACTOR (EGF) AND PLATELET FUNCTlGN BEFORE AND AFTER EXERCISE A. Bodzenta-Lukaszyk, A. Lukaszykl, A. Gabryelewiczl, S. Konturek?, M. Bielawiec Departments of Haematology and I Gastroenterology, Academy of Medicine, Bialystok PL, and 1 Institute of Physiology, Academy of Medicine, Krakow, PL EGF has been found to be associated with blood platelets. It has been also found that the concentrations of salivary, plasma and urinary EGF were increased after prolonged submaximal exercise, when both alpha- and betaadrenergic systems are activated. However, little is known about the role of EGF in platelet function. Therefore, the purpose of this study was to determine, whether serum or plasma EGF released aRer exercise affects bIood platelet function. Six healthy male volunteers, were submitted to a submaximal bicycle ergometry test. Blood for platelet function studies and determination of EGF concentrations was taken via the intravenous cathteter before starting exercise and after 15.30 and 60 minutes rest. A similar scheme was followed to investigate changes in the same parameters induced by a slow intravenous infusion of 0.3 mg/kg b.w. phentolamine (PHEN). Re.sults: The platelet count dropped significantly 30 min after exercise whereas I5 and 60 min after exercise there were no significant changes in platelet count. Following exercise the platelet count was never influenced by administration of PHEN. While evident increase of ADP and adrenaline (ADR) induced platelet aggregation (15 and 30 and 60 min after exercise) was noticed, the platelet aggregation induced by arachidonic acid (AA) and PAF was almost unchanged. Infusion of PHEN markedly increased the TAC of ADR only in the aggregation test. There were no significant changes in plasma TXB, level 15 and 30 min after exercise while 60 min after of little increase in TXB, level was noted. PHEN infusion does not affect plasma level of TXB, after exercise. EGF concentrations in serum and plasma were raised 15 min after exercise. Infusion of PHEN markedly increased the EGF concentrations in serum and plasma ( I5 and 30 min after exercise). These results show that exercise causes a fall in platelet count accompanied by the increase in ADP- and ADR-induced platelet aggregability and the increment in plasma EGF suggesting a close interaction between EGF and platelet function.