Current triton X-100 treatments do not allow a complete plasminogen activator extraction from developing nervous tissue

• Published in: Neurochemical research 1995-02, Vol.20 (2), p.137-142
• Main Authors: PEREYRA-ALFONSO, S, SCICOLONE, G, FISZER DE PLAZAS, S, SAAVEDRA, J. P, FLORES, V
• Format: Article
• Language: English
• Subjects: Aging - physiology; Animals; Biochemistry and metabolism; Biological and medical sciences; Central nervous system; Chick Embryo; Chickens; Embryonic and Fetal Development; Fibrinolysis; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Enzymologic; Octoxynol; Plasminogen Activators - biosynthesis; Plasminogen Activators - isolation & purification; Plasminogen Activators - metabolism; Tectum Mesencephali - embryology; Tectum Mesencephali - enzymology; Tectum Mesencephali - growth & development; Ultracentrifugation - methods; Vertebrates: nervous system and sense organs
• ISSN: 0364-3190; 1573-6903
• DOI: 10.1007/BF00970537

Determinations of plasminogen activator (PA) activity are usually performed in Triton X-100-treated tissue homogenates or crude membrane fractions. Such preparations usually involve a single Triton X-100 treatment. In the present paper we describe the pattern of variability of PA activity measured in different fractions obtained from the developing chick CNS by a repetitive procedure of Triton X-100 treatment and ultracentrifugation. To further characterize this PA activity we have also performed zymographic analyses during the embryonic development and the early postnatal life. Our results show that: a) a single Triton X-100 treatment does not completely extract the enzyme and this lead to an underestimation of the total PA activity; b) the PA activity is associated with the particulate component of the total tissue homogenate requiring its complete solubilization more drastic Triton X-100 treatments; c) better estimations of total and specific activities are obtained by using soluble fractions derived by ultracentrifugation from Triton X-100-treated membrane fractions; d) the developing chick optic lobe expresses only one kind of PA molecule along the entire development; e) the level of PA activity vary characteristically during the ontogeny and the early postnatal life indicating the existence of a developmentally regulated mechanism of PA expression.