Artest and Ariza both scored 15 points in their first meeting since they swapped teams in July. Ariza signed with Houston about the same time Artest left the Rockets to join the Lakers.
Both downplayed how much the game meant to them.
"I was only here one year and really didn't do nothing," Artest said. "I didn't expect anything but to come out here and see Kobe get his 50."
But neither could resist the urge to taunt his former team after hitting a clutch 3-pointer in the final minute of regulation.
Artest's 3 from the top of the key with 30 seconds left gave the Lakers a 92-89 lead. As the Rockets walked to their bench for a time out, Artest stood at midcourt and made a mocking timeout signal of his own to the booing fans.
Ariza was tied up in the lane at the other end, then won a jump ball against Derek Fisher with 19.6 seconds left. Ariza quickly got the ball back from Carl Landry and swished a 3-pointer from the wing with 14.2 seconds left. The Lakers called timeout and Ariza held up three fingers for the Los Angeles bench to see.
"It was poetic justice that they both had excellent opportunities to try and help their team win," Lakers coach Phil Jackson said.
Bryant had the ball in the final seconds of regulation, but Hayes slapped it out of bounds with 0.7 seconds left. The Rockets knocked away the long inbound pass as time expired.
Bryant hit a jumper from the free-throw line with 90 seconds left in overtime. He was fouled by Scola and hit the free throw for a 100-98 lead.
Aaron Brooks sliced through the lane for a layup with 1:06 to go to tie it again. Bryant missed a baseline shot, but Bynum rebounded, got fouled and sank two free throws with 44.2 seconds left to put the Lakers back in front.
Landry hit a hook shot with 37 seconds remaining, ensuring that the Rockets would get one more possession. Bynum was fouled by Hayes and hit one of two free throws with 24.7 seconds left.
Ariza ended up with the ball again in the final seconds of overtime, but Fisher stripped the ball and time ran out.
The Lakers were outrebounded 54-48, but forced 20 Houston turnovers. The Rockets also shot only 29 percent from 3-point range (7 for 24).
Artest guarded Ariza from the opening tip, and the two were immediately jawing at one another. They earned offsetting technical fouls with 9:11 left in the first quarter.
At one point, Ariza said Artest tried to put his hand around Ariza's neck.
"I don't have hard feelings," Ariza said. "It was emotional, I guess you could say."
Artest said he thought about giving Ariza a hard shot, but backed down for fear of a fine or a suspension.
"You know if somebody hits me, I'm going to react," the famously temperamental Artest said. "I got hit with about three elbows. It's just not fair. I don't want to fight, I don't feel like doing it. If you throw an elbow into Ron Artest's chest, do you know who you're hitting?
"But I give up, I just give up," he said. "I'm not fighting anymore. You could elbow me, smack me, use me as a punching bag. I'm not reacting anymore, I'm tired."
Bryant sank four of his first six shots, but the rest of the Lakers missed eight of their first nine and Houston built an 18-10 lead.
Ariza continued to struggle, missing six of his first eight shots, but Landry went 6 for 6 from the field in the second quarter and Houston led 48-44 at the break.
Bryant scored 17 points in the first half, but missed five of his next eight shots after the hot start.
- Injured Lakers C Pau Gasol could return to practice as early as Thursday after sitting out the first five games with a strained right hamstring. "We'll have a limited practice as it is, with back-to-back games," Jackson said. "There won't be a whole lot of activity, but he should be out there."
- Rockets rookie F Chase Budinger sat out with a sprained left ankle. Budinger scored 17 points in Houston's 113-96 victory at Utah on Monday.
- Hall of Famer Hakeem Olajuwon had a courtside seat next to team owner Leslie Alexander.