Sub Gras()
Dim col$, c As Range, s, i%, n%
col = "J"
Columns(col).Cells.Font.Bold = False
On Error Resume Next 'à cause de la cellule fusionnée
For Each c In Columns(col).SpecialCells(xlCellTypeConstants)
c.Characters(1, Len(Split(c, vbLf)(0))).Font.Bold = True
s = Split(c, vbLf & vbLf)
i = 1
For n = 1 To UBound(s)
i = i + Len(s(n - 1)) + 2
c.Characters(i, Len(Split(s(n), vbLf)(0))).Font.Bold = True
Next
Next
End Sub