Acute bouts of high-intensity intermittent exercise (HIIE) or sports are associated with changes in lymphocytes and platelet functions and we hypothesized that the purinergic system is involved with these alterations. We investigated the activity of ectonucleotidases in platelets and lymphocytes as well as the platelet aggregation of futsal players in response to an acute protocol of HIIE. Thus, 19 male semi-professional futsal players were submitted to 40 min of HIIE on a treadmill. Blood samples were collected three-time points: before exercise, immediately after, and 30 min after the end of the session. Platelet-rich plasma (PRP) and lymphocytes were isolated. ATP, ADP, AMP, and adenosine hydrolysis, NTPDase1 (CD39) expression as well as platelet aggregation were measured. Our results showed HIIE induced a decrease in ATP and ADP hydrolysis in platelets, an increase in adenosine hydrolysis and an increase in platelet aggregation immediately after exercise. After 30 min of recovery, enzymatic activity and platelet aggregation returned to baseline levels. In lymphocytes, adenosine hydrolysis was augmented immediately after exercise and remained increased even after 30 min of recovery. In conclusion, acute HIIE triggers a transient proaggregant status that is reverted after a 30 min of recovery. The effects of HIIE in lymphocytes remained after 30 min of recovery, indicating a pro-inflammatory response. This work elucidated some of the mechanisms by which purinergic system regulates lymphocytes and platelets activities related to HIIE, suggesting that the type of exercise may influence an increase in platelet aggregation even in trained individuals.
Keywords: Athletes; ectonucleotidases; intense physical exercise; purinergic system.