觀賞魚紅蓮燈（Paracheirodon axelrodi）真皮虹彩細胞之超微結構

Ultrastructural Study of the Dermal Iridophores on Aquarium Fish Cardinal Tera (Paracheirodon axelrodi)

張銘煌(Ming-Huang Chang) ； 黃銓珍(Chang-Jen Huang) ； 郭宗甫(Tzong-Fu Kuo)

《臺灣獸醫學雜誌》 Volume 28 Issue 3 (2002/09) Pp. 195-203

https://doi.org/10.7009/TVJ.200209.0195

Abstracts

本研究以觀賞魚紅蓮燈為實驗動物，利用組織學及電子顯微鏡術，對紅蓮燈皮膚可發彩虹色澤之虹彩細胞進行形態學研究。結果發現：於肉眼及解剖顯微鏡下，配合光線激發可清楚見到於軀體兩側之中央帶發出以藍色為主，且夾雜綠色、黃色、草綠色、紅色、粉紅色為輔之彩虹色帶，分佈範圍由嘴角延伸至尾鰭前方；彩虹帶內及上方有大量呈星狀或點狀樣之黑色素細胞分佈，而其下方則有大量星狀樣之紅色素細胞存在；發出彩虹色之虹彩細胞與黑色素細胞交織分佈著。彩虹色區經固定液固定後，仍可見到彩虹色，雖然組織切片下無法辨別虹彩細胞之所在，但仍可見黑色素細胞位於真皮之膠原層中。電子顯微鏡下，可見虹彩細胞分佈於真皮層及鱗片之下，且與黑色素細胞交織分佈著。虹彩細胞外形為無特定或近似長形細胞。細胞膜具雙層之單膜。細胞核呈長橢圓形且位於細胞膜旁，核膜亦具雙層單膜之構造；核內可見核仁；核質內有正染色質及異染色質存在，高電子密度之異染色質主要分佈於核周處，其他區域則以低電子密度之正染色質組成，使得細胞核呈淡染樣。粒線體具有雙層界膜及脊構造。細胞內富含大量平行且緊密排列之折射小板由高爾基氏體之分泌泡伸出，折射小板長度約為2-7.5μm，寬度約為40-80 nm。折射小板由高電子密度及低電子密度之折光物質組成。將以本研究結果，進一步探討虹彩細胞內蛋白質組成及其於激發彩虹色澤效應上所扮演之角色。

Keywords

紅蓮燈 ； 真皮 ； 虹彩細胞 ； 超微結構

Parallel abstracts

The aim of this study is to analyze the ultrastructure of dermal iridophores on Cardinal tera (Paracheirodon axelrodi) by means of histological technique and transmission electronic microscopy. Observed from naked eyes or anatomical microscope, a mixture of chromatophore types, illuminated by light, was mainly composed of blue but blended with green, yellow, red, and pink on the intermediate lane of lateral side of the fish body from the mouth angle to the part before tail fin. Within the iridophores lane and at the dorsal region, melanocytes prominently scattered all over like bits and pieces; however, at ventral region, much erythrophores was distributed. The color of chromatophores may be observed by the fixation of 10% neutralized formalin. Although the site of chromatophores was hardly distinguished, the melanophores located within the dermis comprising stratum spongiosum and stratum compactum could still be found. Observed under electron microscope, iridophores, interweaved with melanophores, was distributed within the dermis and under the scales. The profile of iridophores was unspecific and was similar to long type. Cell membrane and nuclear membrane were composed of double unit membranes. Nucleus was in the shape of long ellipse and located beside cell membrane. The nucleolus, euchromatin and heterochromatin were within nucleus. Heterochromatin, preserved in highly condensed electrons, was distributed closely to the perinucleus. The other large regions of euchromatin, preserved in low-condensed electrons, made the nucleus lightly stained by 2% uranyl acetate and lead citrate. There were double limiting membranes and cristaes in mitochondria. Reflective micropletelets, which were numerously contained within cytoplasm and were arranged closely in parallel, protruded from the secretory vesicles of Golgi apparatus. Reflective micropletelets, about 2 to 7.5 μm long and about 40 to 80 nm wide, were composed of reflective substance preserved in low and high-condensed electrons.

Parallel keywords

Cardinal Ters ； Dermis ； Iridophores ； Ultrastructure