中文摘要：

对中华绒螯蟹中肠和后肠肠壁分别进行分层铺片,应用乙酰胆碱酯酶（Ach E）和NADPH-黄递酶组织化学染色方法分别观察中肠和后肠中Ach E和一氧化氮合酶（NOS）阳性神经元的分布和形态,并对其相应递质乙酰胆碱（Ach）和一氧化氮（NO）的含量和Na^＋,K^＋-ATP酶活性进行测定。结果显示：1对所获得铺片进行形态学观察发现,中肠肌层较后肠薄,肌纤维较细,肌纤维间隔明显;肠道黏膜下层细胞分布密集,后肠黏膜下层细胞分布较中肠更为密集。2Ach E和NOS阳性神经元广泛分布于中肠和后肠的黏膜下层,而肌层和基膜未见分布,两种神经元在后肠黏膜下层的分布均较中肠密集。Ach E阳性产物为棕色沉淀,阳性神经元大小为3~10μm,中肠中Ach E形态多样,多为圆形、卵圆形或梭形;后肠胞体阳性神经元呈圆形或者椭圆形,无明显胞突。NOS阳性产物为蓝色沉淀,阳性胞体的大小不等,呈不同形态,少量细胞有胞突伸向邻近细胞,中肠阳性神经元多呈条状或点状分散分布,而后肠阳性神经元常呈块状分布。3中肠Ach和NO含量分别为（1.28±0.41）和（1.84±0.25）μg/mg prot,显著低于后肠Ach（1.62±0.27）μg/mg prot和NO（2.10±0.25）μg/mg prot,而Na^＋,K^＋-ATP活性在中肠为（1.12±0.17）μmol Pi/（mg prot·h）,显著高于后肠的（0.62±0.18）μmol Pi/（mg prot·h）。研究表明,中华绒螯蟹肠道黏膜下层是Ach E和NOS阳性神经元分布的部位,两种神经元递质含量和Na＋,K＋-ATP酶活性在中肠和后肠间存在显著差异。

英文摘要：

The specific dynamic action in intestine is an important factor affecting transit time of food and feeding frequency,and can even influence the growth and development of decapod crustaceans. Moreover,that the midgut and hindgut of crustaceans perform different functions has also been proved. Nowadays,it is widely accepted that acetylcholinesterase（ Ach E） and nitric oxide synthase（ NOS） positive neurons play an important role in the enteric nervous system of mammals. However,such studies in crustaceans are still rare. The aim of the present study was to clarify the distribution and morphological characteristics of Ach E and NOS positive neurons throughout the E.sinensis midgut and hindgut using histochemistry,and to analyse the content of Ach and NO and Na＋,K＋-ATP enzyme activity of midgut and hindgut in E. sinensis by biochemical method. As far as we know,this is the first study in which whole-mount preparations of intestinal walls of midgut and hindgut in E. sinensis were respectively made and stained with HE. The results showed that muscle layers,submucosa and basement-membrane layers were successfully obtained and observed in this study. Compared to the hindgut,the midgut muscle layer consisted of thin muscle fiber with obvious muscle fiber spacing. Submucosas of midgut and hindgut were made up of various cells. These cells were more abundant in the submucosa of hindgut than in midgut. Without obvious cell structure,basement-membrane was thin and transparent. Ach E-positive neurons and NOS-positive neurons were distributed densely only in the submucosa,especially in hindgut. The Ach E-positive neurons were colored brown,which ranged from 3 to 10 μm in size. The shapes of Ach E-positive neurons in midgut were various,most of them were round,oval or spindle shape. The NOS-positive neurons with different sizes and shapes were colored blue. A few of these cells with cytoplasmic projections could be observed. The contents of Ach and NO and Na＋,K＋-ATP enzyme activity in midgut were obviously differ