title: Platelet characteristics change with aging: role of estrogen receptor beta.
abstract: Estrogen receptor beta (betaER) is the predominant estrogen receptor in platelets. Experiments were designed to define phenotypic changes in platelets with aging following deletion of betaER (betaERKO). Blood was collected from wild-type and betaERKO female mice at 4-7 (young) and 24-25 (aged) months of age. In young animals, total number of platelets, number of platelets containing RNA (reticulated platelets), aggregation, dense body adenosine triphosphate secretion, and alpha granular secretion were the same in both groups. With aging, total number of platelets decreased but reticulated platelets increased in betaERKO mice; aggregation and dense granule adenosine triphosphate secretion decreased whereas basal expression of fibrinogen receptors increased with age in wild-type and betaERKO mice. Basal expression of P-selectin and annexin V binding increased with aging only in betaERKO mice; thrombin did not increase expression in these mice. Therefore, deletion of betaER is associated with specific platelet functions, which are expressed only with age-associated reproductive senescence.
authors.affiliation: Department of Surgery, Physiology and Biophysics, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905. miller.virginia@mayo.edu.
authors.forename: Muthuvel
authors.initials: M
authors.lastname: Jayachandran
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Karnicki
authors.forename: Randall S
authors.initials: RS
authors.lastname: Miller
authors.forename: Whyte G
authors.initials: WG
authors.lastname: Owen
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Korach
authors.forename: Virginia M
authors.initials: VM
authors.lastname: Miller
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000375:Aging / Q000502:physiology*; D000818:Animals; D017304:Annexin A5 / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D047629:Estrogen Receptor beta / Q000502:physiology*; D005260:Female; D005434:Flow Cytometry; D017353:Gene Deletion; D051379:Mice; D008810:Mice, Inbred C57BL; D019007:P-Selectin / Q000494:pharmacology; D010641:Phenotype; D010974:Platelet Aggregation; D010976:Platelet Count; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D039341:Receptors, Fibrinogen / Q000096:biosynthesis
chemical_list: D017304:Annexin A5; D004791:Enzyme Inhibitors; D047629:Estrogen Receptor beta; D019007:P-Selectin; D012333:RNA, Messenger; D039341:Receptors, Fibrinogen; D000255:Adenosine Triphosphate