A West Coast surgeon went on trial in federal court here today for the second time this year on charges of paying $36,500 to a government doctor in Bethesda to recommend approval of the potentially lucrative drug DMSO.

The first trial of both doctors -- Oregon surgeon Stanley W. Jacob and Food and Drug Administration official K.C. Pani -- ended in a hung jury last May.

Late last week, Pani, 64, now retired from the FDA, pleaded guilty to a misdemeanor charge of receiving an outside supplement to his government salary for official services. He will be sentenced later this year.

Jacob, in going on trial a second time, faces more serious charges of conspiracy and giving gratuities.

Prosecutors told jurors today that between 1974 and 1979, Jacob paid Pani $36,500 to use his influence to obtain FDA approval of DMSO--dimethyl sulfoxide, an industrial solvent -- to treat a variety of human illnesses including interstitial cystitis, a rare bladder disease, and scleraderma, a connective tissue disorder causing thickening of the skin.

DMSO has been approved only for bladder disease so far. Prosecutors James A. Rothschild and Richard E. Dunne III contended Pani, as the FDA medical officer assigned to evaluate DMSO, developed a close personal friendship with Jacob and thus compromised his job as a regulator of Jacob's drug.

Defense attorney Bernard Fensterwald acknowledged the two men were friends but countered that $16,000 of the $36,500 Jacob gave Pani was a contribution to a medical foundation in Pani's native India. The rest, he said, was a loan -- since paid back -- to help Pani pay huge medical bills for his wife, who died from diabetes in 1977.

While a brilliant surgeon, Jacob was naive in fiscal matters, Fensterwald said.

Jacob, 58, a principle discoverer of DMSO as a drug for human illnesses, is a "compulsive philanthropist" and a humanitarian with a zealot's mission to bring DMSO into worldwide use to help curb suffering, Fensterwald said. DMSO, he said, has already been approved in Europe and South America for a wide range of uses, including rheumatism and muscular and nerve problems.

A Utah-based company called Research Industries Corp. formally petitioned the FDA for DMSO approval in 1974. It paid Jacob, an associate professor of surgery at the University of Oregon Health Science Center in Portland, to be its clinical monitor of DMSO testing by the FDA. Jacob also became a member of the board of directors of Research Industries.

It was as a monitor that Jacob paid Pani the $36,500, the prosecutor said. Pani was one of four FDA officers assigned to evaluate DMSO's safety and effectiveness and to recommend whether it should be approved by higher officials.