Hiromu Akai

Light and electron microscopic studies of the effects of ecdysterone upon the epidermal cells of the larva of the silkworm, Bombyx mori.

Abstract Light microscopic observations indicate that within 12 hr after ecdysterone injection the inner layer of the endocuticle is digested and that new epicuticle is laid down within 18 hr. At 24 hr the formation of the exocuticle is recognizable. Electron microscopic studies show that dense granules appear in the endocuticle at 9 hr after hormone injection and that the lamellae around them are disorganized. At 12 hr the new epicuticle formation commenced on the surface of the epidermis and at 15 hr the formation of the epicuticle can be observed. The results obtained are correlated with previous biochemical studies (Kimura, 1973a, b).

Fine structure of the liquid fibroin of silkworm, Bombyx mori, during its spinning period.

吐糸している蚕の液状フィブロインの走査型電子顕微鏡観察及び見掛けの吸光度の測定からその微細構造を検討した. その結果, 直径1～2μmの球状構造が後部及び中部糸腺の液状フィブロインに, 直径5～10μmの液胞が中部糸腺の液状フィブロインに観察された. 液胞の形成は液状フィブロインの濃度約16%以上で現れた.