Construction has begun on Artery Plaza, a 282,000-square-foot office complex at the corners of Wisconsin and Bethesda avenues at the southern gateway of Bethesda.

The $45 million complex, which includes the Artery Organization's headquarters, is designed in tiers, and is intended to reflect the emerging urbanism of Bethesda's new central business district.

The building is being developed and built by the Artery Organization Inc. The project architect is CHK/Architects and Planners with leasing and management by Charles E. Smith Management Inc. Occupancy is scheduled for next June.

Other recent developments in commercial realty in the Washington metropolitan area:

* Carley Capital Group has chosen the Gilbane Building Co. as construction manager for Henderson's Wharf, a mixed-use development to be located on Baltimore's Inner Harbor.

The $14.9 million project will renovate the historical warehouse building into 53 condominium units totaling 70,000 square feet. The six-story structure also will include 141 inn rooms, a 7,000-square-foot restuarant/lounge, meeting rooms, 3,000 square feet of retail space, and a 200-car parking garage. RTKL Associates Inc. of Baltimore is the project architect.

* The American Enterprise Institute will establish its new headquarters in the top five floors of 1275 Pennsylvania Ave. NW. AEI has signed a 40-year lease and is planning a major funding effort to secure permanent financing for the new headquarters.

The developer, Pennsylvania Building Associates, plans extensive renovation of the interior and the exterior of the 13-story structure. The group plans to occupy the building next summer. CAPTION: Picture, Architect's model of $45 million Artery complex to be completed next June.