Abstract
BACKGROUND: Hormone replacement therapy (HRT) has been associated with an increased risk of venous thrombosis, but effects on platelet function are unknown. OBJECTIVE: To measure the effects of HRT on ex-vivo platelet activation (Plt Act) and aggregation (Plt Ag) using available methods in parallel. METHODS: Women (n=16, x̄ age=57 yrs) on HRT (estrogen 0.625-1.25 mg ± a progestin) for ≥6 mos underwent platelet testing on HRT, then re-testing after 8-12 wks off HRT. Plt Act (basal, +ADP 100um, +Epinephrine 500um [Epi]) was measured in whole blood via flow cytometry using monoclonal antibodies to the activation-dependent marker P-selectin (CD62). Plt Ag and ATP release in response to collagen and other agonists was measured via whole blood lumiaggregometry (L-A), and via the Platelet Function Analyzer® (PFA). Results were analyzed using non-parametric methods. RESULTS: On HRT, ex vivo platelets demonstrated a significant increase in CD62 expression in response to Epi: median 6.3% (range 2.6-21.9%) vs. 5.0% (range 1.5-13.1%) (p=.02, Wilcoxon). Three of four with the highest Epi-stimulated CD62 expression were taking the highest estrogen doses. No differences were observed in basal or ADP-stimulated CD62 expression, in L-A in response to collagen, arachidonic acid, ristocetin or thrombin, or in PFA closure times. CONCLUSIONS: These data suggest that HRT may result in increased platelet reactivity to the physiological agonist epinephrine, possibly contributing to a pro-thrombotic state.
| Original language | English (US) |
|---|---|
| Journal | Journal of Investigative Medicine |
| Volume | 47 |
| Issue number | 2 |
| State | Published - Feb 1999 |
Fingerprint
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
Cite this
Effects of post-menopausal hormone replacement therapy on ex-vivo platelet activation & aggregation. / Aspry, K. E.; Paglieroni, T.; Gosselin, R.; Kappagoda, C. T.; Wun, Theodore.
In: Journal of Investigative Medicine, Vol. 47, No. 2, 02.1999.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of post-menopausal hormone replacement therapy on ex-vivo platelet activation & aggregation
AU - Aspry, K. E.
AU - Paglieroni, T.
AU - Gosselin, R.
AU - Kappagoda, C. T.
AU - Wun, Theodore
PY - 1999/2
Y1 - 1999/2
N2 - BACKGROUND: Hormone replacement therapy (HRT) has been associated with an increased risk of venous thrombosis, but effects on platelet function are unknown. OBJECTIVE: To measure the effects of HRT on ex-vivo platelet activation (Plt Act) and aggregation (Plt Ag) using available methods in parallel. METHODS: Women (n=16, x̄ age=57 yrs) on HRT (estrogen 0.625-1.25 mg ± a progestin) for ≥6 mos underwent platelet testing on HRT, then re-testing after 8-12 wks off HRT. Plt Act (basal, +ADP 100um, +Epinephrine 500um [Epi]) was measured in whole blood via flow cytometry using monoclonal antibodies to the activation-dependent marker P-selectin (CD62). Plt Ag and ATP release in response to collagen and other agonists was measured via whole blood lumiaggregometry (L-A), and via the Platelet Function Analyzer® (PFA). Results were analyzed using non-parametric methods. RESULTS: On HRT, ex vivo platelets demonstrated a significant increase in CD62 expression in response to Epi: median 6.3% (range 2.6-21.9%) vs. 5.0% (range 1.5-13.1%) (p=.02, Wilcoxon). Three of four with the highest Epi-stimulated CD62 expression were taking the highest estrogen doses. No differences were observed in basal or ADP-stimulated CD62 expression, in L-A in response to collagen, arachidonic acid, ristocetin or thrombin, or in PFA closure times. CONCLUSIONS: These data suggest that HRT may result in increased platelet reactivity to the physiological agonist epinephrine, possibly contributing to a pro-thrombotic state.
AB - BACKGROUND: Hormone replacement therapy (HRT) has been associated with an increased risk of venous thrombosis, but effects on platelet function are unknown. OBJECTIVE: To measure the effects of HRT on ex-vivo platelet activation (Plt Act) and aggregation (Plt Ag) using available methods in parallel. METHODS: Women (n=16, x̄ age=57 yrs) on HRT (estrogen 0.625-1.25 mg ± a progestin) for ≥6 mos underwent platelet testing on HRT, then re-testing after 8-12 wks off HRT. Plt Act (basal, +ADP 100um, +Epinephrine 500um [Epi]) was measured in whole blood via flow cytometry using monoclonal antibodies to the activation-dependent marker P-selectin (CD62). Plt Ag and ATP release in response to collagen and other agonists was measured via whole blood lumiaggregometry (L-A), and via the Platelet Function Analyzer® (PFA). Results were analyzed using non-parametric methods. RESULTS: On HRT, ex vivo platelets demonstrated a significant increase in CD62 expression in response to Epi: median 6.3% (range 2.6-21.9%) vs. 5.0% (range 1.5-13.1%) (p=.02, Wilcoxon). Three of four with the highest Epi-stimulated CD62 expression were taking the highest estrogen doses. No differences were observed in basal or ADP-stimulated CD62 expression, in L-A in response to collagen, arachidonic acid, ristocetin or thrombin, or in PFA closure times. CONCLUSIONS: These data suggest that HRT may result in increased platelet reactivity to the physiological agonist epinephrine, possibly contributing to a pro-thrombotic state.
UR - http://www.scopus.com/inward/record.url?scp=33750129046&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33750129046&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:33750129046
VL - 47
JO - Journal of Investigative Medicine
JF - Journal of Investigative Medicine
SN - 1081-5589
IS - 2
ER -