Hola, algo asi
Option Explicit
Private Declare Function PostMessage Lib "user32" Alias "PostMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Const VK_RETURN = &HD
Private Const WM_KEYDOWN = &H100
Private Const WM_KEYUP = &H101
Private Const VK_F5 = &H74
Private Sub Command1_Click()
Call PostMessage(&H30312, WM_KEYDOWN, VK_F5, 0&)
Call PostMessage(&H30312, WM_KEYUP, VK_F5, 0&)
End Sub
en &H30312, tenes que poner el Handle de la ventana del IE, lo podes obtener con la api FindWindow...
saludos.