Abstract: The invention relates to cyclised peptides corresponding to sequence SEQ ID No1: X1X2RGDX3FGX4X5LLFIHFX6IGSX7HSX8IX9, wherein: the letters without any numerical index correspond to amino acids defined by the single-letter international code; X1 is G or GG having an amino-terminal end which may or may not be free; X2 is either a C, in which case X2=X4, the two Cs being connected by a disulphide bridge, or X2 is capable of forming a lactam bridge with X4, either X2 or X4 being an amino acid bearing an acid group, such as A or D, and the other bearing an amino function such as Q, N; X3 is either an M pattern or a norleucine pattern; X5 is one or several di-, tri-, or tetra-peptide patterns comprising G or a combination of G and S, or X5 is a C pattern having a side-chain which serves as a covalent linkage point with a 3-nitro-2-pyridinesulphenyl group which is located at the N-terminal end of the next amino acid (L); X6 is either an R pattern or a K pattern; X7 is either an R pattern or a K pattern; X8 is either