Method for treating cystic fibrosis

A method for identifying a CFTR-binding compound comprising contacting a putative CFTR-binding compound with polypeptide Iα [SEQ ID NO:1] under conditions sufficient to allow for binding of said putative CFTR-binding compound to said polypeptide Iα, and determining whether such binding occurred, an indication that said putative CFTR-binding compound is a CFTR-binding compound.

A method of treating cystic fibrosis in a mammal in need of such treatment, comprising administering a therapeutically effective amount of a compound having the formula

• 4
• wherein R1 and R3 are the same and are C1-C6 alkyl or C1-C6 alkenyl, R7 is C1-C6 alkyl or hydrogen, and R8 is C4-C8 cycloalkyl, and wherein the Ki with respect to said compound and an adenosine receptor is at least 0.01.

A compound having the formula

• 5
• wherein (a) R1 and R3 are the same and are methyl or allyl, R7 is ethyl, cyclopropylmethyl or hydrogen, and R8 is cyclohexyl, provided that R1 is allyl when R7 is hydrogen and R1 is methyl when R7 is ethyl or cyclopropylmethyl, or (b) R1 and R3 are both methyl, and R7 is hydrogen or methyl, and R8 is cyclohexyl-methyl or cycloheptyl.

A pharmaceutical composition comprising a pharmaceutically acceptable carrier and a compound having the formula

• 6
• wherein (a) R1 and R3 are the same and are methyl or allyl, R7 is ethyl, cyclopropylmethyl or hydrogen, and R8 is cyclohexyl, provided that R1 is allyl when R7 is hydrogen and R1 is methyl when R7 is ethyl or cyclopropylmethyl, or (b) R1 and R3 are both methyl, and R7 is hydrogen or methyl, and R8 is cyclohexylmethyl or cycloheptyl.

A polynucleotide selected from the group consisting of polynucleotide Iα [SEQ ID NO:2], polynucleotide Iβ [SEQ ID NO:5], and polynucleotide Io [SEQ ID NO:6].