How to change the Model data being displayed in GridMvc?

I have a GridMvc in my form where it displays a list of units, in this grid has a text field, and a checkbox, I would like when the user type some text box or flag the check, that change reflects on the model. / p>

View:

     <b>Selecione as Unidades</b><div class="code-cut">
        @Html.Grid(Model).Columns(Columns =>
   {
       Columns.Add()
                .Encoded(false)
                .Sanitized(false)
                .SetWidth(30)
                .RenderValueAs(o => Html.CheckBox("Selecionado", o.Selecionado));
       Columns.Add(c => c.IdUnidadeSAP).Titled("ID Unidade SAP").Filterable(true);
       Columns.Add(c => c.Codigo).Titled("ID Unidade Legado").Filterable(true);
       Columns.Add(c => c.Descricao).Titled("Desc. Unidade").Filterable(true);
       Columns.Add(c => c.CodPrestadorSAP).Titled("Cod. Prestador SAP").Filterable(true);
       Columns.Add()
       .Encoded(false)
       .Sanitized(false)
       .SetWidth(30)
       .RenderValueAs(c => Html.TextBox("Cod. Prestador VAEL", c.TipoLogradouro));

   }).WithPaging(10).Sortable(true)
    </div>

Screen: