* Prices rise after debt ceiling extended * Fears of potential debt default priced out of market * Global growth concerns add bid for Treasuries By Karen Brettell NEW YORK, Jan 23(Reuters) - U.S. Treasuries prices edged up on Wednesday after a vote by the House of Representatives to extend the borrowing authority under the federal debt limit to May, and as some investors worried that growth is likely to remain tepid. The Republican debt ceiling plan will allow the government to keep borrowing money through mid-May, putting it on a fast track to enactment after the top Senate Democrat joined the White House in endorsing it. Market concern about the failure to raise the debt ceiling had been ebbing in the past week as Republicans appeared more reluctant to use the measure as a tactic to win cuts in government spending. "I think that was widely anticipated, there was certainly sentiment over the last couple of weeks that things were going to move in that direction," said Greg Faranello, a Treasuries trader at Societe Generale in New York. Some fears over a potential debt default were last week being priced into Treasuries bills due in late February and in March, when the Treasury had warned it would run out of measures to avoid hitting the debt ceiling. Those bills have now largely erased their earlier yield increases. "The biggest issue was political dysfunction. When you push it back by three months not only does it take care of the immediate problem, it also sends a signal that the next time this becomes an issue they will probably do it again," said Amrut Nashikkar, an analyst at Barclays in New York. "Unless things get much worse in terms of the dialogue that is coming out of DC, the debt ceiling itself is unlikely to be an issue," he said. Benchmark 10-year notes were last up 5/32 in price to yield 1.83 percent, down from 1.84 percent late on Tuesday. Thirty-year bonds rose 4/32 in price to yield 3.02 percent, little changed from Tuesday. The bonds earlier tested the key 3 percent level, where the debt has technical resistance. Some concerns that global growth will stay sluggish also added a bid to Treasuries on Wednesday. The International Monetary Fund on Wednesday said that unexpectedly stubborn euro zone recession and weakness in Japan will weigh on global economic growth this year before a rebound in 2014 that should deliver the fastest expansion since 2010. "Japan, Europe and the U.S. are struggling to find something more than 'surface growth,' and that is leading investors to hedge their hopes by taking some risk off the table in the form of U.S. Treasuries," said Kevin Giddis, managing director of fixed income at Morgan Keegan in Memphis, Tennessee. Disagreement among voting members of the Federal Reserve over when to end its latest quantitative easing effort has led to speculation that the central bank may end the program before year end. Fed Chairman Ben Bernanke, however, has said he wants the U.S. economy to be on a surer footing before ending purchases. Minutes from the Fed's January meeting will be released next Wednesday. Other closely watched events will include jobless claims due on Thursday, and next Friday's payrolls employment report for January. Any surprise from these events may move Treasuries out of their current range. Ten-year notes yields have traded between 1.80 percent and 1.91 percent this month. "I think the market is looking for a new catalyst to break either way. There are some events that could potentially shake us one way or another but right now when you look at the Fed, it's still buying on a day to day basis," said Faranello. The Fed on Wednesday bought $1.474 billion of U.S. government debt maturing February 2036 through May 2042, out of $5.72 billion submitted for purchase.