Giant jaguars, menacing serpents and other chillingly beautiful ancient ritual objects lurked among the more than 200 people from international business and politics gathered to celebrate the exhibition "Art of Aztec Mexico: Treasures of Tenochtitlan." The 90 pre-Columbian objects have a macabre history--most of them were used in the prodigious human sacrifices of the ancient Aztecs.

The exhibition, which opens today in the East Building, is a joint project of the National Gallery and Dumbarton Oaks, Harvard University's center for the study of Byzantine and pre-Columbian cultures, and was sponsored by GTE Corp. Deputy Secretary of State Kenneth Dam read a letter from President Reagan and said, "Peace and understanding cannot be imposed by some abstract system like the law . . . it grows from cultural sharing."

The black-tie crowd made society small talk among monumental ritual sculptures with names like "Head of Xipe Totec (Flayed Our Lord)" and "Monster Deity," before being summoned by trumpet fanfare to a dinner of pumpkin soup, filet mignon and Montan a de caramelo.

National Gallery director J. Carter Brown told of making several trips to Italy to persuade the Museo Nazionale Preistorico-Etnografico of Rome and government authorities to release a particularly rare and delicate turquoise mosaic mask. "I arranged my whole schedule to return to Rome, just to get these fabulous pieces," Brown said.

"It turned out to be the week just preceding the elections. The current minister of culture had promised the objects to us, but then he went out of office, creating a whole new set of problems . . . My strategy was based on my belief that the pieces were obscure . . . Well, I was in a phone booth arranging the meetings, and my eyes dropped to the telephone book, and, lo and behold, there were the objects on the cover of the Rome telephone book!" The turquoise objects were ultimately last-minute additions to the show, arriving three days before yesterday's preview.

Sen. Edward Zorinsky (D-Neb.) and his wife Cece discussed their recent visit to the famed archeological museum at Mexico City. "It's a wonder that such beautiful objects came from themes of death or violence," said Zorinsky, who was standing before a grimacing stone skull titled "Macabre Spirit of a Woman Who Has Died in Childbirth."

Exhibition designer Mark Leithauser, who said he was reading the gruesome historical novel "Aztec," said one piece, the colossal jaguar (a vessel for human hearts), weighs nine tons, outranking Rodin's eight-ton "Gates of Hell" as the heaviest work to be installed at the East Building.

"I must admit, I know pre-Columbian art only in a very amateur way," admitted new National Gallery curator Sidney Freedberg, whose field is 16th and 17th century Italian art. "My generation was the first to be exposed to this ethnographic material as art--not just as archeological curiosities."