title: Does cytosolic free calcium concentration in platelets reflect tone and structural changes of resistance vessels?
abstract: To investigate tone and vascular changes of resistance vessels as related to cytosolic free calcium concentration [( Ca2+]i) in platelets, we measured forearm vascular resistance and free calcium concentration in platelets from 10 essential hypertensives and 15 normotensives. The [Ca2+]i in platelets was significantly higher in essential hypertensives than in normotensives (184 +/- 43 versus 146 +/- 23 nmol/l, P less than 0.01). The [Ca2+]i levels in platelets were significantly correlated with both systolic (r = 0.50, P less than 0.05) and diastolic blood pressures (r = 0.57, P less than 0.01). Resting vascular resistance and minimal vascular resistance were significantly higher in essential hypertensives than in normotensives (30.6 +/- 12.6 and 2.57 +/- 1.30 versus 16.3 +/- 8.0 and 1.47 +/- 0.63 mmHg/ml per min per 100 ml, P less than 0.05 and P less than 0.01, respectively). Both resting and minimal vascular resistance were significantly correlated with [Ca2+]i in platelets (r = 0.40 and P less than 0.05, r = 0.55 and P less than 0.01, respectively). These results suggest that [Ca2+]i in platelets reflects [Ca2+]i in vascular smooth muscle cells and may be a significant determinant of not only tone but also structural changes of resistance vessels.
authors.affiliation: Second Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ueno
authors.forename: M
authors.initials: M
authors.lastname: Mikawa
authors.forename: M
authors.initials: M
authors.lastname: Takata
authors.forename: H
authors.initials: H
authors.lastname: Asanoi
authors.forename: H
authors.initials: H
authors.lastname: Iida
authors.forename: S
authors.initials: S
authors.lastname: Sasayama
authors.forename: S
authors.initials: S
authors.lastname: Kagamimori
mesh_terms: D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D008875:Middle Aged; D014655:Vascular Resistance
chemical_list: D002118:Calcium