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Research Article Free access | 10.1172/JCI105630
Department of Medicine, New York Hospital-Cornell Medical Center, and the New York Veterans Administration Hospital, New York
‡Send reprint requests to Dr. Ralph L. Nachman, the New York Hospital-Cornell Medical Center, 525 East 68th Street, New York, N. Y. 10021.
*Submitted for publication November 28, 1966; accepted May 9, 1967.
Supported by grants from the National Institutes of Health (HE-09070-03 and C-1905), the Veterans Administration, the New York Heart Association, and the R. A. Hummel Memorial Fund of New York Hospital.
Presented in part at the annual meeting of the American Society for Clinical Investigation, Atlantic City, May 3, 1966. An abstract appeared in the Journal of Clinical Investigation 1966, 45, 1050.
Find articles by Nachman, R. in: JCI | PubMed | Google Scholar
Department of Medicine, New York Hospital-Cornell Medical Center, and the New York Veterans Administration Hospital, New York
‡Send reprint requests to Dr. Ralph L. Nachman, the New York Hospital-Cornell Medical Center, 525 East 68th Street, New York, N. Y. 10021.
*Submitted for publication November 28, 1966; accepted May 9, 1967.
Supported by grants from the National Institutes of Health (HE-09070-03 and C-1905), the Veterans Administration, the New York Heart Association, and the R. A. Hummel Memorial Fund of New York Hospital.
Presented in part at the annual meeting of the American Society for Clinical Investigation, Atlantic City, May 3, 1966. An abstract appeared in the Journal of Clinical Investigation 1966, 45, 1050.
Find articles by Marcus, A. in: JCI | PubMed | Google Scholar
Department of Medicine, New York Hospital-Cornell Medical Center, and the New York Veterans Administration Hospital, New York
‡Send reprint requests to Dr. Ralph L. Nachman, the New York Hospital-Cornell Medical Center, 525 East 68th Street, New York, N. Y. 10021.
*Submitted for publication November 28, 1966; accepted May 9, 1967.
Supported by grants from the National Institutes of Health (HE-09070-03 and C-1905), the Veterans Administration, the New York Heart Association, and the R. A. Hummel Memorial Fund of New York Hospital.
Presented in part at the annual meeting of the American Society for Clinical Investigation, Atlantic City, May 3, 1966. An abstract appeared in the Journal of Clinical Investigation 1966, 45, 1050.
Find articles by Safier, L. in: JCI | PubMed | Google Scholar
Published August 1, 1967 - More info
Thrombosthenin, an immunologically distinct contractile protein was isolated in relatively pure form from human platelets. The protein, which was of high molecular weight appeared to be composed of multiple polypeptide subunits, probably polymeric in nature.
Thrombosthenin had magnesium-dependent ATPase activisty, releasing an average of 3 μg phosphorus per mg protein in 30 min. After the addition of ATP, there was a reversible alteration in viscosity with calculated ATP sensitivity ranging from 64 to 90%. These biochemical properties of thrombosthenin resemble those of smooth muscle.
Specific antisera to thrombosthenin significantly inhibited the ATPase activity of the protein. Clot retraction of recalcified platelet-rich plasma and clot retraction of clotted fibrinogen-platelet mixtures were also inhibited by the antisera. The findings suggest that thrombosthenin is an important component of the clot retraction system.
Thrombosthenin was extracted from isolated platelet granule and membrane fractions. The contractile protein derived from the membrane compartment was more active as an ATPase and appeared to be more homogeneous on immunologic analysis.
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