Robbie Henshaw has signed a contract extension with Connacht that will see him play at the Sportsground until at least 2016.
Tommy O'Donnell has signed a two-year contract extension with Munster and the Ireland Rugby Football Union.
A late Jimmy Gopperth penalty saw Leinster narrowly escape with a 21-20 win against Treviso at the Stadio Monigo.
Three first-half tries from Munster helped them overcome a struggling Cardiff Blues 31-10.
It was an unhappy return to Ravenhill for Edinburgh coach Alan Solomons as Ulster cruised to a comfortable 47-17 victory.
Round Eight of the Pro12 kicks off on Friday night with both Scottish teams in action - one home and one away.
Loosehead prop Tom Court will leave Ulster at the end of this season after he agreed a new long term contract with Premiership club London Irish.
Wales and Scarlets centre Jonathan Davies has signed a two-year contract with Clermont, the French Top 14 club announced on Tuesday.
Glasgow continued their 100 percent away-day start to the Pro12 season.
Cardiff Blues captain and former Welsh skipper Matthew Rees is continuing his battle with cancer.