Method of screening remedy for renal failure
A screening tool and a convenient screening method for obtaining a renal failure treating agent, and a pharmaceutical composition for treating renal failure and a production method thereof are disclosed. The aforementioned screening tool is a G protein coupling type receptor FGK which is a polypeptide capable of activating CTGF promoter, a functionally equivalent modified substance thereof or a homologous polypeptide, or a cell expressing the aforementioned polypeptide. The screening method is a method which employs inhibition of the aforementioned polypeptide as the index.
1 . A screening tool for an agent for treating renal failure, which is a polypeptide consisting of the amino acid sequence represented by SEQ ID NO:2, or a polypeptide comprising an amino acid sequence represented by SEQ ID NO:2 in which from 1 to 10 amino acids are deleted, substituted and/or inserted and which is capable of activating CTGF promoter.
2 . The screening tool for an agent for treating renal failure, which is a cell expressing the polypeptide described in claim 1 .
3 . A method for detecting whether or not a test compound is an inverse agonist, which comprises
a step of allowing the cell described in claim 2 co-expressing a chimeric G protein in which C-terminal amino acid sequence is the amino acid sequence represented by SEQ ID NO:16, and which is a chimera of a partial polypeptide having promoting activity of phospholipase C activity of a phospholipase C activity-promoting G protein with a partial polypeptide having a Gi receptor coupling activity, to contact with a test compound, and
a step of analyzing a change in activity of the polypeptide described in claim 1 in said cell.
4 . A method for screening an agent for treating renal failure, which comprises
a step of allowing the cell described in claim 2 co-expressing a chimeric G-protein in which C-terminal amino acid sequence is the amino acid sequence represented by SEQ ID NO:16, and which is a chimera of a partial polypeptide having promoting activity of phospholipase C activity of a phospholipase C activity-promoting G protein with a partial polypeptide having a Gi receptor coupling activity, to contact with a test compound, and
a step of analyzing a change in activity of the polypeptide described in claim 1 in said cell.
5 . A method for screening a substance inhibiting expression of CTGF, which comprises
a step of allowing the cell described in claim 2 expressing the DNA of SEQ ID NO:13 having a reporter gene in downstream to contact with a test compound, and
a step of measuring the reporter activity in said cell.
6 . The screening method according to claim 5 , wherein the substance inhibiting expression of CTGF is an agent for treating renal failure.
7 . A method for screening an agent for treating renal failure, which comprises
a step of allowing the cell described in claim 2 expressing the DNA of SEQ ID NO:14 having a reporter gene in downstream to contact with a test compound, and
a step of measuring the reporter activity in said cell.
8 . A pharmaceutical composition for treating renal failure, which comprises an inverse agonist for the polypeptide described in claim 1 .
9 . A pharmaceutical composition for treating renal failure, which comprises a substance obtainable by the method according to one of claim 4 to claim 7 .
10 . A method for producing a pharmaceutical composition for treating renal failure, which comprises
a step of screening using the method according to one of claim 4 to claim 7 , and
a step of preparing a pharmaceutical composition using a substance obtained by said screening.
11 . A method for treating renal failure, which comprises administering an effective amount of an inverse agonist for the polypeptide described in claim 1 and/or a substance obtaiable by the method according to one of claim 4 to claim 7 to a subject in need of the treatment of renal failure.
12 . Use of an inverse agonist for the polypeptide described in claim 1 and/or a substance obtainable by the method according to one of claim 4 to claim 7 for the manufacture of a pharmaceutical composition for treating renal failure.