A drive begun last year to increase mortgage lending in some low-income neighborhoods of Prince George's County has resulted in few real gains -- largely because many buyers were discouraged by high interest rates, a community group reports.

The study was made by Neighborhoods Uniting Project, an organization seeking to increase stability as well as racial and economic integration in communities.

Members of the group include representatives of community organizations and church groups in 13 towns and communities in northwest Prince George's inside the Beltway. The targeted areas are Mt. Rainier, Brentwood, North Brentwood, Cottage City, Colmar Manor, Chillum, West Hyattsville, Hyattsville, Riverdale, East Riverdale, Edmonston, Rogers Heights and Bladensburg.

The organization's president, Edward Pariseau, said the drive was begun last year after a couple complained that they were turned down for a mortgage loan on a house in Riverdale. The couple reported that they were told by Perpetual Federal Savings and Loan Association, the biggest local S&L, that "we don't mortgage in that area," Pariseau said.

It is against federal regulations for a federally chartered lending institution to refuse a home mortgage loan solely on the basis of the location of the dwelling.

Perpetual President Thomas Owen denied that the remark about the area had been made, and said that the loan was turned down for other reasons. But he acknowledged that the case "wasn't handled as carefully as it should have been."

After the couple complained, NUP officials met with Owen and other Perpetual executives. This resulted in an agreement to try to increase lending activity in the county, Pariseau said.

A Perpetual mortgage specialist and Pariseau said that, generally, Perpetual has lived up to the terms of the agreement reached with NUP last November.

A Perpetual brochure explaining loan procedures and requirements is being readied for distribution and the S&L is training an additional mortgage loan officer, a spokesman said. Advertisements soliciting loan applications have been placed; reports on lending activities are being made periodically to the community group; contacts are maintained with organizations inside the Beltway, and other elements of the agreement are being met, he added.

Besides Perpetual, two other large mortgage lenders in the county -- Maryland Federal Savings and Loan Associations and Suburban Trust Co., a commercial bank -- were included in the survey of recent lending.

The community group noted a wide discrepancy in the number of mortgage loans made in Prince George's by Perpetual and Suburban Trust when compared with the number made in neighboring Montgomery County where incomes are higher. The counties have roughly the number of single-family homes.

But the community group found that in 1978 and 1979 Maryland Federal made substantially more conventional loans in Prince George's than in Montgomery.

Figures for Maryland Federal, an old Prince George's institution, show that 305 mortgage loans were made in that county in 1978, compared with 101 in Montgomery. Last year the figures were 159 for Prince George's and 101 for Montgomery.

Neighborhoods Uniting Project figured that roughly 36 of the 305 loans that Montgomery Federal made in 1978 were for inner Beltway towns and communities. No breakdown was available for 1979.

Robert N. Halleck, executive vice president of Maryland Federal, blamed the 1979 decline in loan activity on widespread withdrawals of funds to invest elsewhere at higher rates of interest.

"We just didn't have the money," Halleck said. He was hopeful that declining interest rates for home loan mortgages would brighten the picture for Maryland Federal.

After consultation with Neighborhoods Uniting Project, Maryland Federal last year made available to all communities inside the Beltway in Prince George's $2.5 million for mortgage loans at 12 percent interest, then about 2 percentage points below the going rate. The money was snapped up in six weeks, Maryland Federal officials said.

In 1978 Perpetual Federal made 204 conventional loans in Prince George's and 924 in Montgomery. Of the Prince George's total, 35 were in the inner Beltway area, the organization said.

From November 1978 through last November, Perpetual closed 131 loans in Prince George's, said David Freed, Perpetual mortgage specialist. Figures for Montgomery County were not available, he said.

Freed provided figures to show that Prince George's residents lagged behind Montgomery County residents in applying for loans.

"From November 1979 through this past April 1, Montgomery County provided 35 percent of loan applications received from the entire metropolitan area," Freed said. "Prince George's provided only 6.8 percent."

Of the total loans made by Perpetual in the metropolitan area, 40 percent were in Montgomery and 7.85 percent were in Prince George's. Of the loans refused, 23 percent were in Montgomery and 8.6 percent were in Prince George's.

Freed said percentages rather than numerical totals were given "for marketing reasons." He said he did not wish to disclose details of Perpetual's loan activities to competitors.

Loans in the metropolitan area generally were down because of high interest rates, he said. There has been a 41 percent decline during the fiscal year that began last November, compared with the preceding period, he said.

In 1978, Suburban Trust made 195 mortgage loans in Prince George's and 612 in Montgomery, the community group said. Of the Prince George's loans, 29 were in the inner-Beltway area.

R. Blair Richards, Suburban vice president and manager of its mortgage loan department said he did not have a county-by-county breakdown of loan figures for 1979. He said reports are made on a census tract basis. To break the figures down into more specific areas would require too much time and staff work, he said.

The neighborhoods association is attempting to do this but the result is not yet available, Pariseau said.

Richards said he did not know why a disproportionate number of loans were made to Montgomery residents, but cited the greater volume of building in Montgomery as one possible reason.

"We are a commercial bank," Richards said. "Mortgages are not our primary business and our interest rates are a little higher." He said the bank has been cooperating with community organizations in Seat Pleasant and Baltimore.

Pariseau said that the neighborhoods group is planning to approach Suburban Trust, Maryland Federal and other lending institutions for an agreement similar to that concluded with Perpetual.