Blood coagulation time prolonging agent

Abstract

Provided is a reagent, which prolongs a blood coagulation time sufficiently and enhances an optical change, thereby enabling a correct and high-sensitive blood coagulability test. The present invention provides a blood coagulation time prolonging agent, including, as an active ingredient, a guanidine compound represented by the following formula (1) or an acid addition salt thereof (in the formula, R 1 represents a hydrogen atom, an amino group, or an alkyl group which may have a substituent).

1 - 21 . (canceled) 
     
     
         22 . A method of measuring blood coagulation, comprising:
 (a) adding to a plasma specimen a guanidine compound represented by formula (1) or an acid addition salt thereof:   
       
         
           
           
               
               
           
         
         wherein R 1  represents a hydrogen atom, an amino group, or an alkyl group which may optionally have a substituent; 
         (b) adding to the plasma specimen a blood coagulation activator,
 wherein the blood coagulation activator induces the formation of a network of fibrin in the plasma specimen, 
 wherein the network of fibrin in the plasma specimen increases turbidity in the plasma specimen, and 
 wherein the guanidine compound represented by formula (1) or an acid addition salt thereof enhances turbidity in the plasma specimen and prolongs the blood coagulation time; and 
 
         (c) measuring a change, ΔH, in the scattered light intensity from the plasma specimen to determine the coagulation time of the plasma specimen. 
       
     
     
         23 . The method of  claim 22 , wherein R 1  represents a hydrogen atom, an amino group, an alkyl group, an alkyl group substituted with a carboxy group and an amino group, or an alkyl group substituted with an alkoxycarbonyl group and an amino group. 
     
     
         24 . The method of  claim 22 , further comprising adding a specimen diluent to the plasma specimen when adding the guanidine compound represented by formula (1) or an acid addition salt thereof: 
     
     
         25 . The method of  claim 22 , wherein the blood coagulation activator comprises thrombin. 
     
     
         26 . The method of  claim 22 , wherein the guanidine compound represented by formula (1) or an acid addition salt thereof is guanidine or an acid addition salt thereof. 
     
     
         27 . The method of  claim 22 , wherein guanidine compound represented by formula (1) or an acid addition salt thereof is guanidine hydrochloride.