* Moody's may cut Morgan Stanley's, Goldman's ratings

* Morgan Stanley shares trim losses with market

* Credit protection costs rise to 24 percent upfront

* Mitsubishi UFJ may seek to renegotiate deal terms-CNBC

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By Christian Plumb and Joseph A. Giannone

NEW YORK (Reuters) - Mitsubishi UFJ Financial Group Inc (MUFG) (8306.T: Quote, Profile, Research) could seek to renegotiate the terms of a planned $9 billion cash injection into investment bank Morgan Stanley (MS.N: Quote, Profile, Research), CNBC reported on Friday, even as sources told Reuters the deal was still on track to close on Tuesday.

Unidentified people at Morgan Stanley, whose shares ended down 22 percent after earlier losing more than double that, also said it was possible that the U.S. Treasury could end up taking a stake in the firm, CNBC reported. [nWEN9034]

Even if the deal does close, there were some questions whether the MUFG investment would be enough to let the company, whose ratings Moody's Investors Service has said it might cut, ride out the current storm.  Continued...