Newcastle owner Mike Ashley is a shareholder at Rangers – with an 8.92% stake.
Newcastle quintet Haris Vuckic from Slovenia, English defender Remie Streete, Burundi-born Gael Bigirimana, Swiss defender Kevin Mbabu and Northern Ireland international winger Shane Ferguson have now joined the Ibrox club until the end of the campaign.
The Newcastle website reported: "Burundi-born Bigirimana, aged 21, joined United from Coventry in July 2012 and has made 26 first team appearances for the Magpies.
"This season he has been a mainstay of Peter Beardsley's table-topping U21 side.
"Ferguson, 23, has been sidelined this campaign so far after suffering a knee injury in the early part of the season.
"The 17-times capped Northern Ireland international, who has 32 first-team games for Newcastle under his belt, spent the majority of last season on loan at Birmingham City.
"Nineteen-year-old Mbabu is a Switzerland U19 international who has yet to make the breakthrough to first team football but has impressed with a number of confident defensive displays at second-string level.
"Streete made his Football League debut with Port Vale earlier this season. The 20-year-old centre half has been on the bench for the first team this term but has yet to make his senior bow for United.
"Vuckic is a 22-year-old Slovenian with one full international cap, which came against Scotland in 2012, to his name.
"He has made 32 first team appearances for the Magpies, scoring once, since making his debut back in August 2009."