Russia has increased interest rates to offset instability. Once external factors like the price of oil settle, and the Russian economy nears bottom, interest rate cuts will be needed to stimulate the recovery. This will encourage investment and counteract inflationary trends. Combined with lower interest, other stimulus like increased trade will be essential for the Russian economy to recover.
Russia is in a tough spot. Too much of their economy is still reliant on energy exports and very vulnerable to oil price swings, as we have seen lately. With the weakness of the ruble as of late they don't have a lot of room to move in cutting interest rates.
Russia will not have to cut interest rates to save their economy. Unfortunately the current state of affairs is a part of a larger issue; however, Russia has a large enough economy that it can weather most storms. Also the Russian population can withstand the pressures put on it by outsides forces. Russia will sell oil and services to fringe nations before it cuts its interest rates.
Interest rate changes will not do a thing to save the Russian economy. This is because the banks will still be receiving less money even if people do pay up on their loans. Whether people default because of high interest or pay a much lower interest, the results will mostly be the same.