物理
物理
물리
2014年
5期
330-336
,共7页
钱霞%阮树仁%孙桂芳%盛淑芳
錢霞%阮樹仁%孫桂芳%盛淑芳
전하%원수인%손계방%성숙방
家鸽%磁铁矿%超顺磁%神经组织%磁接收器
傢鴿%磁鐵礦%超順磁%神經組織%磁接收器
가합%자철광%초순자%신경조직%자접수기
homing pigeon%magnetite%superparamagnetic%nerve%magnetoreceptor
磁铁矿可以在很多生物组织中被发现,国外研究者同样在家鸽上喙皮肤组织中发现了规则分布的超顺磁磁铁矿颗粒。他们应用透射电子显微镜确认了这些小磁铁矿晶体为尺寸在1-5 nm的聚集体,集中存在于皮下组织中。这些超顺磁粒子聚集体又形成直径为1-3μm的粒子束,分布在大细胞之间的长形结构中,并且与神经组织紧密相连。应用光学显微镜和电子显微镜,国外研究者也对家鸽上喙传入三叉神经末梢的次细胞组织进行了研究。这些神经末梢组织直径大约5μm,内部包含着聚集成束的超顺磁磁铁矿颗粒。大约10到15个粒子束存在于一个神经末梢中,沿着细胞膜排列。每一个超顺磁粒子束包埋在一个纤维杯中,口朝向细胞表面,通过纤维组织,这些粒子束粘附在细胞表面上。除了超顺磁颗粒,非晶态铁磷酸盐也被发现,它们沿着神经末梢的纤维中心分布。解剖特征表明,这些神经末端可以探测很小的地磁场强度的变化,考虑到以超顺磁磁铁矿颗粒为基础的“磁接收器”理论,他们还给出了几个“磁接收器”的模型。
磁鐵礦可以在很多生物組織中被髮現,國外研究者同樣在傢鴿上喙皮膚組織中髮現瞭規則分佈的超順磁磁鐵礦顆粒。他們應用透射電子顯微鏡確認瞭這些小磁鐵礦晶體為呎吋在1-5 nm的聚集體,集中存在于皮下組織中。這些超順磁粒子聚集體又形成直徑為1-3μm的粒子束,分佈在大細胞之間的長形結構中,併且與神經組織緊密相連。應用光學顯微鏡和電子顯微鏡,國外研究者也對傢鴿上喙傳入三扠神經末梢的次細胞組織進行瞭研究。這些神經末梢組織直徑大約5μm,內部包含著聚集成束的超順磁磁鐵礦顆粒。大約10到15箇粒子束存在于一箇神經末梢中,沿著細胞膜排列。每一箇超順磁粒子束包埋在一箇纖維杯中,口朝嚮細胞錶麵,通過纖維組織,這些粒子束粘附在細胞錶麵上。除瞭超順磁顆粒,非晶態鐵燐痠鹽也被髮現,它們沿著神經末梢的纖維中心分佈。解剖特徵錶明,這些神經末耑可以探測很小的地磁場彊度的變化,攷慮到以超順磁磁鐵礦顆粒為基礎的“磁接收器”理論,他們還給齣瞭幾箇“磁接收器”的模型。
자철광가이재흔다생물조직중피발현,국외연구자동양재가합상훼피부조직중발현료규칙분포적초순자자철광과립。타문응용투사전자현미경학인료저사소자철광정체위척촌재1-5 nm적취집체,집중존재우피하조직중。저사초순자입자취집체우형성직경위1-3μm적입자속,분포재대세포지간적장형결구중,병차여신경조직긴밀상련。응용광학현미경화전자현미경,국외연구자야대가합상훼전입삼차신경말소적차세포조직진행료연구。저사신경말소조직직경대약5μm,내부포함착취집성속적초순자자철광과립。대약10도15개입자속존재우일개신경말소중,연착세포막배렬。매일개초순자입자속포매재일개섬유배중,구조향세포표면,통과섬유조직,저사입자속점부재세포표면상。제료초순자과립,비정태철린산염야피발현,타문연착신경말소적섬유중심분포。해부특정표명,저사신경말단가이탐측흔소적지자장강도적변화,고필도이초순자자철광과립위기출적“자접수기”이론,타문환급출료궤개“자접수기”적모형。
Magnetite can be found in many life forms, including superparamagnetic (SPM) particles in the upper-beak skin of homing pigeons. Using transmission electron microsco-py it has been found that these superparamagnetic particles are concentrated in the subcutis and are identified as aggregates of magnetite nanocrystals with grain sizes between 1 and 5 nm. These particles form clusters of 1-3μm diameter, which are distributed in distinct coherent elongated structures, associated with nervous tissue and located between fat cells. Studies on the subcellular organization of afferent trigeminal terminals in the upper beak of the homing pigeon based on opti-cal and electron microscopy have been reported. They are about 5μm in diameter and contain SPM crystals. The SPM nanocrystals are assembled in clusters , and about 10 to 15 of these clus-ters occur inside one nerve terminal, arranged along the cell membrane. Each SPM cluster is em-bedded in a solid fibrous cup open towards the cell surface, to which the cluster adheres by fiber strands. In addition to the SPM, iron phosphate is also found along a fibrous core of the terminal. The anatomic features suggest that these nerve endings can detect small intensity changes of the geomagnetic field. Several models about SPM based magnetoreceptor have been suggested. In this paper, a brief overview is presented of the above issues.