Increase osmotic pressure would trigger production of Aldosterone which end up causing increase fluid absorption resulting to decrease urine production.
The whole system is called the Renin-Angiotensin-System (RAS) or sometimes Renin-Angiotensin-Aldosterone-System (RAAS)
You should always think about the values and pros and cons before making a major decision to ensure that you are going to make the right decision, and that you'll be happy with your choice.
