Anti-spermatogenic activity of malvidin chloride in langur monkeys (Presbytis entellus entellus Dufresne).

Malvidin chloride (MC) a colouring agent from flowers of Malvaviscus conzattii Greenum was studied for male anti-fertility effects in adult langur monkeys (Presbytis entellus entellus Dufresne). When fed 50 mg MC kg-1 for a period of 60 days, inhibition of spermatogenesis resulted. The weights of testes and epididymides were reduced and there was atrophy of the Leydig cells. In the epididymis, epithelial cell heights were reduced after MC-treatment. Conspicuous shrinkage of seminiferous tubules and Leydig cell nuclei were evident. Depletion of total proteins, RNA, sialic acid, alkaline/acid phosphatase activity in testes and epididymides with the elevation of testicular levels of cholesterol and glycogen also occurred. Blood/serum analysis and haematology of MC-treated langur monkeys revealed that all of the clinically important parameters were well within the normal range. The slightly increased bilirubin concentration and alkaline phosphatase activity returned to normal range within 30 days of the last dose of MC. The anti-spermatogenic activity of MC in langur monkeys is discussed.