In 1886 after a personnel decision by Tokyo University regarding soninkan goyogakari (higher rank officers selected on the recommendation of the Prime Minister), Juntaro assumed the post of full-time lecturer at Tokyo Imperial University Medical School,
明治19年（1886年）東京大学奏任官御用掛の任免を受け東京帝国大学医科大学専任講師に就任。