Specialty lender Fifth Street Asset Management Inc. is exploring a sale amid a deterioration in its loan portfolio and management turnover, the Wall Street Journal reported today. The Greenwich, Conn., company is working with Morgan Stanley to sound out potential buyers, according to people familiar with the matter. The process is in an early stage, and there is no assurance it will yield a transaction. Fifth Street explored a sale last year but failed to come to terms with bidders, the people said. Fifth Street manages $4.7 billion in corporate loans and other investments.