Controls :: Save (Insert) And Retrieve (Display) TinyMCE Contents To Database?

I used tinyMCE in my edit.aspx page that bind it from database 

TextBox1.Text = _dr["description"].ToString();

and users can change this editor text and click on button and update information

below is code

protected void ImageButton2_Click1(object sender, ImageClickEventArgs e)
{
string data = Session["behcode"].ToString();
SqlCommand _cmd = new SqlCommand("insertstate", _cn);
_cmd.CommandType = CommandType.StoredProcedure;
_cn.Open();
_cmd.Parameters.AddWithValue("@Name", txtstore.Text);
_cmd.Parameters.AddWithValue("@Ownername", txtowner.Text);
_cmd.Parameters.AddWithValue("@Description", TextBox1.Text);
_cmd.ExecuteNonQuery();
Session["Message"] = true;
_cn.Close();
} 

in database I have House_info table that has description column and if I enter text in textbox1 it update description column now problem is when I enter text in textbox1 it didn't change text and didn't update data in database...

I put breakpoint in imagebutton2_click event and see in this code

_cmd.Parameters.AddWithValue("@Description", TextBox1.Text);

it didn't send any text from textbox1 and show text that bind from database and didn't change it... so what should I do?