They toasted their husbands "for what they're doing -- wherever they are," then at Nancy Reagan's invitation the wives of President Reagan's Cabinet officers toasted themselves yesterday "for letting them do it."

It was the first lady's first White House luncheon for Cabinet and Cabinet-level wives. Seated at blue-covered tables in the Blue Room, 16 of them and the wife of the vice president celebrated the first anniversary of the president's inauguration.

"I'd like to welcome you all -- a year late," Mrs. Reagan apologized, then chuckling added that "my husband tells me you should never start a speech with an apology."

Describing a year that had been "an emotional roller coaster, so many highs and lows," she said "it wasn't that I wasn't thinking of you all. I was -- off and on I was."

When Barbara Bush rose to make a response, she seemed surprised to find photographers and reporters present, although they were barred by the White House from asking questions.

"When I asked if I could say something," she said, "I thought we were going to be alone."

The year had been a "fabulous" one, said the vice president's wife, recalling how she had vowed to "work my heart out" for Mrs. Reagan after meeting her at the Republican National Convention in Detroit. She told the first lady that her guests at the luncheon would do the same.

"They mean it much more today than I meant it a year and a half ago," she said. ("Thank you for doing that for us," Susan Baker, wife of the Senate majority leader, whispered to Bush later.)

Two Cabinet wives sent their regrets. Marilyn Lewis, a member of the Pennsylvania legislature and wife of the secretary of transportation, had to be in Harrisburg for a vote. Jane Weinberger, wife of the secretary of defense, was out of the country.

Also invited but sending regrets was U.N. Ambassador Jeane Kirkpatrick. Her husband, however, had not been invited, a White House spokeswoman said.

Luncheon fare included spinach and ham souffle', endive salad and a sorbet called "apples in a basket." As mementos, there were enlargements of the Reagans' 1981 Christmas card by Jamie Wyeth, personally inscribed to each guest by Mrs. Reagan.