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Platelet volume and count after severe prolonged physical effort
THROMBOSIS RESEARCH 38; 439-442, 1985 0049-3848/85 $3.00 + .OO Printed in the USA; Copyright (c) 1985 Pergamon Press Ltd. All rights reserved.
MINI REPORT PLATELET VOLUME AND COUNT AFTER SEVERE PROLONGED PHYSICAL EFFORT Y T Kishk, +E A Trowbridge Departments The University
and J F Martin
of Medicine and +Medical Physics and Clinical Engineering, of Sheffield, Royal Hallamshire Hospital, Sheffield SlO 2JF U K
(Received 4.7.1984; Accepted in original form 25.11.1984 by Editor P.J. Gaffney) (Received in final form by Executive Editorial Office 19.2.1985) INTRODUCTION
Short duration exercise has been reported to induce a transient rise in platelet count (PC), (1,2). However it has been suggested that prolonged exercise produces no change in PC (3). Freedman et al (2) reported an exercise-induced thrombocytosis accompanied by an increase in large platelets and a shift in platelet volume distribution in both normal and a-splenic humans. This study investiqates PC and mean platelet volume (MPV) before and after severe prolonged exercise in trained distance runners.
MATERIALS
AND METHODS
This study was carried out on a group of male long distance fell-runners, mean age 30.4 + 2.7 years, who had a mean weight of 68 f 1.4 Kg. Five of them showed expected evidence of left ventricular hypertrophy and strain on electrocardiogram. They all completed the same 13 Km run during which they ascended 300 m in altitude. Their average time of exercise was one hour. Venous
blood samples were taken into sodium citrate and for the measurement of platelet volume distribution and count before an a immediately after exercise. Velocity gradients were used to recover a truly representative sample of the total platelet population compared to whole blood. Mean platelet volume distribution was measured in a resistive particle counter coupled via an analogue to digital convertor to a microcomputer (available from Dr. J.F. Martin) (4). PC was determined as before (4). The samples were run in duplicate.
prostaglandin E
1;ey words:
Platelet
vere physical
effort
count, platelet volume distribution, 439
se-
440
PLATELET VOLUME AND COUNT
Vo1.38, No.4
RESULTS
The PC and MPV before and after exercise
are given in the table.
The recovery of platelets from whole blood before exercise was 102 -+ 3.4% whereas the recovery after exercise was 95.1 -+ 4.2%. There was no significant difference in these values. There was a significant increase paired t test) but no significant change in in the mean PC (p < 0.01, average MPV after exercise.
TABLE 1 Mean Platelet Volume and Count Before and After Exercise in 7 Runners
M P V, fl
PC x 10-11/l
Before Exercise
After Exercise
Mean
6.8
6.9
SE
to.20
+0.20
p value
Before Exercise
After Exercise
2.19
2.53
20.08
kO.08
NS
COMMENT
This study shows that PC was significantly elevated after severe prolonged exercise. However it was not accompanied by a change in MPV. The possible source of elevated PC during exercise is still Some investigators have attributed it to the release of obscure. pre-formed platelets from the pulmonary veins (5) and the spleen (6,7), haemoconcentration or the entry of platelets into the axial blood flow (3). Although a small percentage of the observed increase in PC may be attributed to changes in splenic pooling it is unlikely that the spleen plays a major role in this elevation since post-exercise thrombocytosis has been reported in splenectomized subjects (1,2). Furthermore the reported changes in haemoconcentration are insufficient to account for the observed rise in PC (8).
Vo1.38,
No.4
PLATELET
VOLUME AND COUNT
441
Although it has been reported (3,9) that PC remained unchanged after prolonged exercise we obtained a significant increase in PC in our post-exercise samples. Furthermore the platelets circulating in the blood after severe exercise were not enriched with large platelets as supported observed by Schmidt and Rasmussen (10). This is also contrary to the observations reported by Freedman et al (2) who, on the basis of the assumption that the spleen preferentially retain large platelets (7) explained their observed exercise-induced increase in platelet volume by the release of large platelets mostly from the spleen. It is of interest that Freedman et al (2) used EOTA as an anticoagulant. EDTA is associated with platelet shape change and swelling (11). In our study we used sodium citrate and PGEI to prevent artefacts which can be linked to EDTA. These differences in methodology may account for the results obtained here and in the earlier study by Freedman et al (2). The presence of a nonsplenic pool of platelets which is utilized during exercise has been postulated (2,5). In an earlier study (12) it has been proposed that platelets are formed by random fragmentation of Since circulation. megakaryocytes (MGK) cytoplasm in the pulmonary strenuous physical effort is accompanied by increased circulation velocity, one might speculate that an increased delivery and fragmentation of MGK in the lungs could increase the platelet count (13). Increased migration of MGK into the lungs has been reported during stressful conditions such as acute infections, blood loss and liver insufficiency (14) and after surgery (15). Although pathological conditions are not identical experienced by the runners the to the physical stress observations above show that increased MGK mobilization is a possibility. conclusion, it is possible that a number of factors for haemoconcentration, change in splenic pooling and increased production, none of which are predominant, combine to produce the increase in PC without change in MPV after severe exercise.
In example, platelet observed
ACKNOWLEDGEMENT The authors for their effort.
are grateful to the members of Dark Peak Fell Runners
REFERENCES
Exercise-induced
thrombocytosis.
1.
DAWSON, A.A. and OGSTON, D. Acta Haemat. 42, 241-246, 1969.
2.
FREEDMAN, M., ALTSZULER, N. and KARPATKIN, S. Presence non-splenic platelet pool. Blood. 50, 419-425, 1977.
3.
BENNETT, P.N. Effect of physical exercise adhesiveness. Scan. J. Haemat. 9, 138-141, 1972.
on
of
a
platelet
442
PLATELET VOLUME AND COUNT
Vo1.38, No.4
4.
MARTIN, J.F., TROWBRIDGE, E.A., SALMON, G.L. and SLATER, D.N. The relationship between platelet, and megakaryocyte volumes. Thromb. Res. 28, 447-459, 1982.
5.
BIERMAN, H.R., KELLY, K.H., CORDES, F.L., BYRON, R.L., POLHEMUS, J.A. and RAPPOPORTS, S. The release of leukocytes and platelets from the pulmonary circulation by epinephrine. Blood 7, 683-692, 1952.
6.
WRIGHT, C.S., DOAN, C.A., BOURONCLE, B.A. and ZOLLINGER, R.M. Direct splenic arterial and venous blood studies in hypersplenic syndromes before and after epinephrine. Blood 6, 195-212, 1951.
7.
FREEDMAN, M.L. and KARPATKIN, S. Heterogeneity of rabbit Preferential platelets splenic sequestration of (VI. megathrombocytes. Br. J. Haematol. 3l, 255-262, 1975.
8.
Effect of exercise on platelet WARLOW, C.P. and OGSTON, D. Acta Haemat. 52, 47-52, 1974. count, adhesion, and aggregation.
9.
PEGRUM, G.D., HARRISON, K.M., SHAW, S., HASELTON, A. and WOLFE. S. Effect of orolonqed exercise on olatelet adhesiveness. Nature 213,-301-302, i967. -
10.
SCHMIDT, K.G. and RASMUSSEN, J.W. Are young platelets in excess from the spleen in response to short-term Stand. J. Haematol. 207-214, 1984. exercse
11.
The LEVIN, J. and BESSMAN, J.D. platelet volume and platelet number. 295-307, 1983.
12.
TROWBRIDGE, E.A. MARTIN, J.F., SLATER, D.N., KISHK, Y.T. and a computer based biological Platelet production: WARREN C.W. Thromb. Res. 3l, 329-350, 1983. interpretation.
13.
MARTIN, J.F., SLATER, D.N. and TROWBRIDGE, E.A. intrapulmonary platelets: A possible cause of vascular Lancet 1, 793-796, 1983. disease.
14.
Megakaryocytes in pulmonary blood AABO, K. and HANSEN, K.B. relations vessels. I. Incidence at autopsy, clinicopathological Acta. especially to dissiminated intravascular coagulation. Pathol. Microbial. Stand. A. 86, 285-91, 1978.
15.
BESLOW, A., KAUFMAN, R.M. and LAWSKY, A.R. The effect of surgery on the concentration of circulatory megakaryocytes and platelets. Blood 32, 392-401, 1968.
released physical
inverse relation between J. Lab. Clin. Med. 101,
Abnormal and lung
MINI REPORT PLATELET VOLUME AND COUNT AFTER SEVERE PROLONGED PHYSICAL EFFORT Y T Kishk, +E A Trowbridge Departments The University
and J F Martin
of Medicine and +Medical Physics and Clinical Engineering, of Sheffield, Royal Hallamshire Hospital, Sheffield SlO 2JF U K
(Received 4.7.1984; Accepted in original form 25.11.1984 by Editor P.J. Gaffney) (Received in final form by Executive Editorial Office 19.2.1985) INTRODUCTION
Short duration exercise has been reported to induce a transient rise in platelet count (PC), (1,2). However it has been suggested that prolonged exercise produces no change in PC (3). Freedman et al (2) reported an exercise-induced thrombocytosis accompanied by an increase in large platelets and a shift in platelet volume distribution in both normal and a-splenic humans. This study investiqates PC and mean platelet volume (MPV) before and after severe prolonged exercise in trained distance runners.
MATERIALS
AND METHODS
This study was carried out on a group of male long distance fell-runners, mean age 30.4 + 2.7 years, who had a mean weight of 68 f 1.4 Kg. Five of them showed expected evidence of left ventricular hypertrophy and strain on electrocardiogram. They all completed the same 13 Km run during which they ascended 300 m in altitude. Their average time of exercise was one hour. Venous
blood samples were taken into sodium citrate and for the measurement of platelet volume distribution and count before an a immediately after exercise. Velocity gradients were used to recover a truly representative sample of the total platelet population compared to whole blood. Mean platelet volume distribution was measured in a resistive particle counter coupled via an analogue to digital convertor to a microcomputer (available from Dr. J.F. Martin) (4). PC was determined as before (4). The samples were run in duplicate.
prostaglandin E
1;ey words:
Platelet
vere physical
effort
count, platelet volume distribution, 439
se-
440
PLATELET VOLUME AND COUNT
Vo1.38, No.4
RESULTS
The PC and MPV before and after exercise
are given in the table.
The recovery of platelets from whole blood before exercise was 102 -+ 3.4% whereas the recovery after exercise was 95.1 -+ 4.2%. There was no significant difference in these values. There was a significant increase paired t test) but no significant change in in the mean PC (p < 0.01, average MPV after exercise.
TABLE 1 Mean Platelet Volume and Count Before and After Exercise in 7 Runners
M P V, fl
PC x 10-11/l
Before Exercise
After Exercise
Mean
6.8
6.9
SE
to.20
+0.20
p value
Before Exercise
After Exercise
2.19
2.53
20.08
kO.08
NS
COMMENT
This study shows that PC was significantly elevated after severe prolonged exercise. However it was not accompanied by a change in MPV. The possible source of elevated PC during exercise is still Some investigators have attributed it to the release of obscure. pre-formed platelets from the pulmonary veins (5) and the spleen (6,7), haemoconcentration or the entry of platelets into the axial blood flow (3). Although a small percentage of the observed increase in PC may be attributed to changes in splenic pooling it is unlikely that the spleen plays a major role in this elevation since post-exercise thrombocytosis has been reported in splenectomized subjects (1,2). Furthermore the reported changes in haemoconcentration are insufficient to account for the observed rise in PC (8).
Vo1.38,
No.4
PLATELET
VOLUME AND COUNT
441
Although it has been reported (3,9) that PC remained unchanged after prolonged exercise we obtained a significant increase in PC in our post-exercise samples. Furthermore the platelets circulating in the blood after severe exercise were not enriched with large platelets as supported observed by Schmidt and Rasmussen (10). This is also contrary to the observations reported by Freedman et al (2) who, on the basis of the assumption that the spleen preferentially retain large platelets (7) explained their observed exercise-induced increase in platelet volume by the release of large platelets mostly from the spleen. It is of interest that Freedman et al (2) used EOTA as an anticoagulant. EDTA is associated with platelet shape change and swelling (11). In our study we used sodium citrate and PGEI to prevent artefacts which can be linked to EDTA. These differences in methodology may account for the results obtained here and in the earlier study by Freedman et al (2). The presence of a nonsplenic pool of platelets which is utilized during exercise has been postulated (2,5). In an earlier study (12) it has been proposed that platelets are formed by random fragmentation of Since circulation. megakaryocytes (MGK) cytoplasm in the pulmonary strenuous physical effort is accompanied by increased circulation velocity, one might speculate that an increased delivery and fragmentation of MGK in the lungs could increase the platelet count (13). Increased migration of MGK into the lungs has been reported during stressful conditions such as acute infections, blood loss and liver insufficiency (14) and after surgery (15). Although pathological conditions are not identical experienced by the runners the to the physical stress observations above show that increased MGK mobilization is a possibility. conclusion, it is possible that a number of factors for haemoconcentration, change in splenic pooling and increased production, none of which are predominant, combine to produce the increase in PC without change in MPV after severe exercise.
In example, platelet observed
ACKNOWLEDGEMENT The authors for their effort.
are grateful to the members of Dark Peak Fell Runners
REFERENCES
Exercise-induced
thrombocytosis.
1.
DAWSON, A.A. and OGSTON, D. Acta Haemat. 42, 241-246, 1969.
2.
FREEDMAN, M., ALTSZULER, N. and KARPATKIN, S. Presence non-splenic platelet pool. Blood. 50, 419-425, 1977.
3.
BENNETT, P.N. Effect of physical exercise adhesiveness. Scan. J. Haemat. 9, 138-141, 1972.
on
of
a
platelet
442
PLATELET VOLUME AND COUNT
Vo1.38, No.4
4.
MARTIN, J.F., TROWBRIDGE, E.A., SALMON, G.L. and SLATER, D.N. The relationship between platelet, and megakaryocyte volumes. Thromb. Res. 28, 447-459, 1982.
5.
BIERMAN, H.R., KELLY, K.H., CORDES, F.L., BYRON, R.L., POLHEMUS, J.A. and RAPPOPORTS, S. The release of leukocytes and platelets from the pulmonary circulation by epinephrine. Blood 7, 683-692, 1952.
6.
WRIGHT, C.S., DOAN, C.A., BOURONCLE, B.A. and ZOLLINGER, R.M. Direct splenic arterial and venous blood studies in hypersplenic syndromes before and after epinephrine. Blood 6, 195-212, 1951.
7.
FREEDMAN, M.L. and KARPATKIN, S. Heterogeneity of rabbit Preferential platelets splenic sequestration of (VI. megathrombocytes. Br. J. Haematol. 3l, 255-262, 1975.
8.
Effect of exercise on platelet WARLOW, C.P. and OGSTON, D. Acta Haemat. 52, 47-52, 1974. count, adhesion, and aggregation.
9.
PEGRUM, G.D., HARRISON, K.M., SHAW, S., HASELTON, A. and WOLFE. S. Effect of orolonqed exercise on olatelet adhesiveness. Nature 213,-301-302, i967. -
10.
SCHMIDT, K.G. and RASMUSSEN, J.W. Are young platelets in excess from the spleen in response to short-term Stand. J. Haematol. 207-214, 1984. exercse
11.
The LEVIN, J. and BESSMAN, J.D. platelet volume and platelet number. 295-307, 1983.
12.
TROWBRIDGE, E.A. MARTIN, J.F., SLATER, D.N., KISHK, Y.T. and a computer based biological Platelet production: WARREN C.W. Thromb. Res. 3l, 329-350, 1983. interpretation.
13.
MARTIN, J.F., SLATER, D.N. and TROWBRIDGE, E.A. intrapulmonary platelets: A possible cause of vascular Lancet 1, 793-796, 1983. disease.
14.
Megakaryocytes in pulmonary blood AABO, K. and HANSEN, K.B. relations vessels. I. Incidence at autopsy, clinicopathological Acta. especially to dissiminated intravascular coagulation. Pathol. Microbial. Stand. A. 86, 285-91, 1978.
15.
BESLOW, A., KAUFMAN, R.M. and LAWSKY, A.R. The effect of surgery on the concentration of circulatory megakaryocytes and platelets. Blood 32, 392-401, 1968.
released physical
inverse relation between J. Lab. Clin. Med. 101,
Abnormal and lung