New Orleans bankers plan to buy Tri-State Bank, ending the Memphis firm's 75-year run as the city's high-profile Black-owned bank. Liberty Bank and Trust Co., the nation's third largest Black-owned bank, and Tri-State released a statement Thursday night disclosing the proposed deal. Regulators and Tri-State shareholders must approve the merger for the deal to proceed.  Tri-State, founded in 1946 by insurance executives, stood out as a bank smoothing the way for Black Americans during the period of integration in the 1960s and 1970s but struggled in later decades as a Downtown-oriented bank. Tri-State cut back on its all-important church lending as middle-class wage gains stagnated, Black residents dispersed to neighborhoods throughout the city distant from Downtown, new bus routes bypassed its Main Street location, and many Black families shifted to banking with bigger institutions.