Los Angeles ? There’s no more potent symbol for Hollywood TV executives these days than Peter Griffin’s pixilated buttocks.

That was the image on Fox a few weeks back. The network’s executives ordered a 5-year-old “Family Guy” scene blurred because it was nervous about what the Federal Communications Commission might think of Griffin’s naked rear end — a CARTOON character’s naked rear — on television.

In a separate episode, Fox similarly covered the baby behind of Stewie, Peter’s son. Both were shown with no reaction when “Family Guy” ran initially a half-decade ago.

TV executives are extremely jittery about the FCC these days, concerned that the taste standards they had become used to have become as blurred as Peter’s butt.

And Friday’s resignation of FCC Chairman Michael K. Powell likely will add to their uncertainty. Powell backed a record $7.7 million in indecency fines leveled by the FCC last year, up from $48,000 the year before he became chairman.

“We can’t have a clear view of the FCC guidelines because the FCC guidelines are not clear,” said Gail Berman, Fox entertainment president. “We have to be checking and second-guessing ourselves now, and that’s really difficult. We have to protect our affiliates.”

Each of Fox’s 169 stations was fined $7,000 by the FCC in October for airing an episode of “Married By America” that showed people licking whipped cream from strippers’ bodies and a man in his underwear being spanked by strippers.

The jitters extend well beyond Hollywood, as witnessed by the dozens of ABC affiliates that would not air the Academy Award-winning drama “Saving Private Ryan” last November because of concerns about violence and profanity.

Their critics have little sympathy.

The dysfunctional cartoon Griffin family from the animated series The

“They’re lucky they got away with as much as they did,” said Laura Mahaney, spokeswoman for the conservative watchdogs Parents Television Council. “It reminds me of a person who has been speeding as much as they wanted and now they’re getting tickets.”

Fox may have blurred some rear ends, but Mahaney said a recent “Family Guy” episode left intact a father-son chat about penis size.

The butt-blurring “seems a little extreme,” but “Family Guy” creator Seth MacFarlane said he recognizes the tightrope networks are walking.

“All networks are under enormous pressure from the FCC and we deal with that every day,” he said. “I mean, the phrase ‘in this post-Janet Jackson world’ is kind of bandied about like they’re talking about Sept. 11th.”

CBS, which aired the brief glimpse of Jackson’s breast that started everything a year ago at the Super Bowl, had its own buttocks self-censorship a few weeks ago. An episode of “Without a Trace” showed a naked man running down a street, filmed from behind.

The network ordered the scene cut out, reasoning that “we don’t need that,” said CBS Chairman Leslie Moonves.

CBS is refusing to pay the FCC’s $550,000 fine imposed last fall for Jackson’s famed wardrobe malfunction.

“What we’re saying to our producers is, ‘Guys, let’s not be stupid about this,”‘ Moonves said. “Clearly, there’s a change in how the FCC is looking at us. We’re not changing our content. But by the same token, we have to be aware of what the world is out there.”