Alexander N. Shelepin, 47, one of the bright young men of the Soviet Communist Party, apparently replaced Nikolai V. Podgerny, 62, as number two man in the Party yesterday.

The move puts Shelepin in the role of heir apparent to Leonid I. Brezhnev, who holds the nation's most powerful position as Communist Party First Secretary.

Grand Old Man

Also it was announced that Anastas I. Mikoyan, 70, grand old man of the Bolsheviks after 48 years in Soviet politics, resigned from his largely ceremonial job as President of the Praesidium, the Soviet Parliament, because of ill health. He was replaced by Podgerny.

According to Associated Press dispatches, Shelepin, former head of the secret police, has for some time been regarded as the probably future top man in the Soviet Union.

The AP speculates that Shelepin's appointment, which will allow him to concentrate his energies on party affairs, means that party discipline will be tightened up and that stricter party supervision will be applied to the drive for economic reform within the USSR.

Party Control

Shelepin, who has recently wielded enormous power as head of the committee on party and state control, would be the man for the job, according to the AP.

Merle Fainsod, Carl H. Pforzheimer University Professor, said that there was no specific evidence at the present that Shelepin was stepping into Podgerny's job, but that if he were, "he's certainly stepping into power. As for Podgerny, Fainsod said that "it is quite clear that he's being sidetracked. It's clear that there has been bad blood between him and Brezhnev."

'Kind of Bundy'

Another Russian specialist, who preferred to remain anonymous, confirmed that that was an advancement for Shelepin and a demotion for Podgerny. However, he noted, "if people think he's the heir apparent, chances are he won't assume the throne." He described Shelepin as a man of "cool intelligence." He's a kind of McGeorge Bundy figure, only more sinister," he said.