Abstract
Effects of ergocornine and reserpine on tail resorption during metamorphosis Bufo bufom japonicus tadpoles were studied. At prometamorphosis, ergocornine induced precocious tail resorption, while reserpine scarcely affected the tail size. At the climax of metamorphosis, ergocornine was almost ineffective in accelerating tail resorption, while reserpine was effective in inhibiting tail resorption. Since prolactinlike hormone is known to block the tail resorption induced by thyroid hormones, was postulated that the release of the hormone is blocked by ergocornine during prometamorphosis and stimulated by reserpine during climax.
