PRN Ambulance, a North Hills ambulance service company, has been acquired by a rival patient transport service company.

Terms of the deal announced Tuesday between PRN and ProTransport-1 LLC, based in the Northern California city of Cotati, were not disclosed.

PRN was founded in 2000 by Avo Avetisyan with just three ambulances and grew to a fleet of 60 vehicles and a staff of more than 350 employees.

Avetisyan said that in looking for an acquisition partner, PRN wanted one that added to what it does for patients and hospital customers while preserving the company culture exhibited by the staff.

“I am excited that the PRN name and team will have this opportunity to continue to flourish and I will continue to play a significant leadership role in the combined companies,” Avetisyan said in a prepared statement.

ProTransport-1 is a portfolio company of private equity firm New Heritage Capital, based in Boston. It operates a fleet of 170 vehicles with a staff of more than 900 employees.

Chief Executive Mike Sechrist said the acquisition was an important step in expanding into new geographic areas.

“The Los Angeles market is home to many sophisticated health systems looking for the high-quality and efficient coordination of patients that the ProTransport-1 model provides,” Sechrist said in a prepared statement.