PITTSBURGH — University of Pittsburgh Chancellor Mark Nordenberg has refused a raise, citing economic challenges the school faces, but the board of trustees has approved hikes for six other top administrators.

The trustees approved Nordenberg’s recommendation that his salary be frozen at $561,000 for the coming year.

But six other administrators got raises from 2.3 percent to 4.6 percent on Monday.

Arthur Levine, the senior vice chancellor for health and dean of Pitt’s medical school, got the smallest raise, but will still have the highest salary among the seven administrators who got raises, at $762,000.

Senior vice chancellor and provost Patricia Beeson’s 4.6 percent raise takes her salary to $340,000.

The other administrators will be paid from $208,000 to $475,000.

The school’s state funding dropped $40 million, or 22 percent this year.