Effect of cold pressor test and awareness of hypertension on platelet function in normotensive and hypertensive women

Abstract

Mundal HH, Nordby G, Lande K, Gjesdal K, Kjeldsen SE, Os I. Effect of cold pressor test and awareness of hypertension on platelet function in normotensive and hypertensive women. Scand J Clin Lab Invest 1993; 53: 585-591.

Plasma β-thromboglobulin (J3-TG) concentration, reflecting platelet function in vivo was compared in fertile women with untreated essential hypertension and age-matched normotensives, in two separate studies. In the first study, hypertensives and normotensives were aware of their blood pressure status. Blood was sampled through arterial and venous indwelling catheters, and no difference in β-TG was found between the groups. Arterial /3-TG was significantly lower than venous concentration (p ≤ 0.05). Cold pressor test increased arterial β-TG significantly in both groups (p ≤ 0.05).

In the second study, both women and investigator were unaware of blood pressure status, and /3-TG concentration, platelet count, and mean platelet volume obtained by venipunctures were similar in the hypertensive and normotensive group.

Thus, platelet function in vivo seems to be normal in fertile hypertensive women, in contrast to the platelet dysfunction previously reported in hypertensive men. In women, as in men, platelet release occurred during venous catheter blood sampling and during cold pressor test. However, at variance from men, platelet function was not influenced by awareness of blood pressure status in the hypertensive females.

Key Words:

• beta-thromboglobulin
• blood pressure
• cold pressor test
• female
• platelet count
• platelet volume