menuItemName.ShortcutKeyDisplayString = "Alt+`";
menuItemName.ShowShortcutKeys = false;
Tip: other "OEM" keys you'll have to rename to something more human include: numpad numbers (vs. keypad numbers, left of keyboard), backslash, brackets, operators (OemPlus, OemMinus...), and punctuation marks (OemQuestion - sometimes used for Help menu, OemPeriod...)