Story highlights Larry Flynt: "He was an icon from the beginning of the erotic film industry"

Reems was a pioneer in the fight for First Amendment rights for porn actors, Ron Jeremy says

His obscenity conviction for "Deep Throat" was overturned on appeal

He "found Jesus" and sold real estate in Utah after leaving the adult film industry

Harry Reems, the porn star best known for playing Dr. Young in the 1972 adult film classic "Deep Throat," died Tuesday, according to a spokeswoman at a Salt Lake City hospital. Reems, whose real name was Herbert Streicher, was 65.

Reems, who appeared in numerous pornographic films in the 1970s and '80s, was a pioneer whose battle for First Amendment rights paved the way for the adult film industry to enter the mainstream, said fellow actor Ron Jeremy.

Jill Atwood, spokeswoman for George E. Wahlen VA Medical Center in Salt Lake City, would not disclose the cause of death for privacy reasons.

Reems' big break came in 1972 on the set of "Deep Throat" when the actor cast to play the feisty Dr. Young failed to show up for filming. Reems was promoted from extra to co-star, which meant an unforgettable sex scene with leading lady Linda Lovelace.

The film's budget of $25,000 included just a few hundred dollars for Reems, but the notoriety of the movie -- highlighted by well-publicized legal troubles -- made him one of the top porn stars in the United States in the 1970s.

Reems, who grew up in the New York's Bronx, "was the original," Jeremy said. "It was Reems and John Holmes. They were the biggest names at the time."

"Everyone who has ever seen a porn film knows who Harry Reems is," Hustler magazine publisher Larry Flynt told CNN through his representative. "He was an icon from the beginning of the erotic film industry."

"Deep Throat" went on to make hundreds of millions of dollars after criminal investigations and the prosecution of Reems for obscenity and conspiracy brought it global attention.

His obscenity conviction was overturned on appeal, but the legal battle became an important First Amendment fight for some in Hollywood.

The battle over "Deep Throat" became a "cause celebre," said Paul Fishbein, founder of AVN (Adult Video News).

"Because Harry Reems was famous for 'Deep Throat,' I think people forget he was sort of the face of '70s obscenity," said Fishbein, who is now president of X3Sixty Network, a cable network dedicated to programming about the adult industry. "When he got indicted for that movie, it was a big deal."

Hollywood stars including Jack Nicholson and Warren Beatty supported Reems' defense, Jeremy said.

"It made him a pioneer," Jeremy said.

Reems followed up in 1973 with "Devil in Miss Jones," another rare porn film remembered by many 40 years later.

Reems' Internet Movie Database page lists 139 productions in which he acted between 1970 and 1986, when he left the industry.

Although he aspired as a young man to be a mainstream actor, that goal evaded him in the wake of his porn reputation. He was initially cast to play Coach Calhoun in "Grease," the 1978 smash musical starring John Travolta and Olivia Newton-John, but producers ultimately replaced him with Sid Caesar.

Jeremy spoke fondly of his 1980s friendship with Reems, with memories of hanging out in Bernards, a bar off New York's Times Square that attracted both Broadway and porn actors. It was a hangout where the two men would pick up women and sometimes "go to the bathroom to do a little smoochie."

"We were on a bunch of sets side by side," Jeremy said. "We did threesomes on set a couple of time."

"We were both Jewish boys with a big mustaches," he said. "We both loved doing dialogue in movies, more than just an 'uuuuhh!'"

Reems left the adult movie business in 1987 and moved to Utah, where "somehow he found Jesus and decided to go Mormon," Jeremy said.

"He said he was glad to be far away from it," Jeremey said, referring to the porn industry.

Reems' new career was real estate, which he initially sold using his birth name, Herbert Streicher.

Eventually, though, he decided to use his famous name to sell real estate. "Maybe he wasn't selling enough," Jeremy said. "He used Harry Reems, and business was booming."

Jeremy said Reems' death was not a shock because he had known his health was deteriorating.

Reems' friends plan a memorial on Saturday after a performance of a stage play that tells his infamous story -- "Deep Throat Sex Scandal" -- at the Zephyr Theatre in West Hollywood, California, Jeremy said.