OSAKA -- A heart transplant recipient, one of a series of patients who received organ transplants on Wednesday and Thursday, showed signs of recovery after undergoing an emergency operation following the transplant, doctors said.

Doctors at Osaka University Hospital in Suita, Osaka Prefecture, said the 8-year-old male recipient regained a steady pulse and his heart started pumping more and more blood beginning around noon.

The patient was in serious condition at one stage on Thursday after a second operation -- which he underwent to maintain the transplanted heart's functions after it began beating too rapidly -- resulted in low blood pressure due to the heart's inability to pump out blood.