The Australian actor and singer, currently starring in Joseph and The Amazing Technicolor Dreamcoat until Saturday (July 30), played Scott Robinson in the show, which is airing its final episode in the UK on Friday (July 29), making his first appearance in 1986.
Tweeting on Friday from Blackpool, he simply said: “ ‘That’s when good neighbours become good friends...’ neighbours 1985-200”, adding a heart emoji.
Speaking to BBC Radio 4's Today programme, Donovan, 54, said: "I'm extremely proud of those 37 years that Neighbours shone a light on our culture, that wasn't just a blown-up fictitious version like the Crocodile Dundees.
"It showed the everyday life of how Aussies live.
"It kept a lot of people in my industry employed and developed talent.
"You never forget your roots. To see today the amount of talent that has come back to Neighbours shows just how much that show meant to them."
Reflecting on the musical success of a number of his co-stars, including Kylie Minogue, Holly Valance and Natalie Imbruglia, Donovan said: "When you have a platform like that [Neighbours], even when you look at something like The X Factor, how it creates a story. Neighbours did that.
"It created a story about Scott and Charlene that then people invested [in] if the music was right in that person.
"Something like what Natalie did with Torn, it sort of fitted her character of Beth."
The Australian soap, which has been on screens for 37 years, will draw to a close with an extended final episode on Channel 5 on Friday evening.
Donovan, Minogue, 54, and Guy Pearce were among the celebrities who returned to Ramsay Street to appear in the send-off of the Melbourne-based drama that helped launch their careers in acting and music.
In quotes released by Channel 5 ahead of the finale broadcast, Minogue said: "It feels amazing, surreal and very emotional. We worked with the director we worked with back in the 80s so a few familiar faces. Same houses, same street - there is no easy answer, just a mix of emotions, but very happy. Very aware of the moment."
The Australian actor and singer starred as Charlene Robinson in the soap, making her first appearance in 1986, and she reprises her role for one last time in the finale.
"Charlene was such a presence in people's memory," she said. "I wasn't sure how it would work. Neighbours wrapping up has put a completely different spin on all of it - it opened the door for this to happen. I didn't really see it happening but now it has, it feels good."
She added of her character's trademark look: "The curls are just as big, and the mousse is back!"
Delta Goodrem, who starred as Nina Tucker in the show, has also spoken about the "beautiful connection" formed between the cast members.
Speaking to BBC Breakfast, Goodrem, 37, recalled her experience on Neighbours as "an honour and a blessing", and explained the importance of being able to learn from the variety of cast members she worked with.
"To even have the tiniest part in something that has been a part of our lives is an honour and a blessing," she said.
"It really was a masterclass, you left school and then you went to Erinsborough High and that was really where I got my education from... It was a place where there was great learnings, great discipline, where you were learning all the time around actors [who] had been there for years and years."
Amid waning ratings, the cancellation of the show was announced in March after it lost its key UK broadcast partner and failed to secure alternative funding.
Goodrem said: "It's definitely really tugging on all our heartstrings.
"I think the fact that so many of us have come back, it's because it's a home... it's been there throughout all of our lives."
The final episode has already aired in Australia and it drew the biggest TV ratings for Channel Ten in 13 years, according to Deadline.
It reported that an average of 1.2 million Australian viewers nationally tuned in to watch the finale, with a peak of 1.4 million.
Joseph and the Amazing Technicolor Dreamcoat at Blackpool
Jason Donovan is currently reprising his role as Pharoah for the third time in the new production of Tim Rice and Andrew Lloyd Webber’s classic musical at Blackpool Winter Gardens’ Opera House from Monday July 25 to Saturday July 30, 2022.
He performed the role at the London Palladium in 2019 and 2021 and he will be sharing the stage again with Linzi Hateley as the narrator and Jac Yarrow as he prepares to don the famous coat in the titular role as Joseph on tour.
Linzi is an Olivier Award nominee and Theatre World Award winner who has starred on Broadway, in the West End, with the RSC, and at the National Theatre. She now returns to the role of the Narrator, having first starred in Joseph and the Amazing Technicolor Dreamcoat in 1991 opposite Jason Donovan and Phillip Schofield at the London Palladium – for which she received an Olivier Award nomination for Best Actress in a Musical.
Jac made his professional stage debut playing Joseph, following in the footsteps of a line of stars who have previously played the title character. His portrayal of Joseph won him unanimous acclaim and an Olivier Award nomination, with his rendition of ‘Close Every Door To Me’ regularly stopping the show with standing ovations.