王锦蛇心的位置及其组织学参数和胶原纤维含量的增龄变化

为阐明王锦蛇(Elaphe carinata)心的位置、组织学参数和胶原纤维含量的发育可塑性,采用形态测量、苏木精-伊红染色和Masson染色方法,测定了1龄、2龄以及50日龄内王锦蛇个体身体大小和心位置,同时测定并分析了50日龄内个体心内膜、心肌层和心外膜的厚度,以及胶原纤维含量的增龄变化。王锦蛇的体重、体全长和体重与体全长的比值都在2龄组最高,1龄组其次,2和1龄组均显著高于50日龄内各组(P<0.05)。肥满度3日龄组和7~10日龄组都显著高于1和2龄组(P<0.05)。心与吻端的距离,1和2龄组都显著高于其他日龄组(P<0.05),但心与吻端的距离与体全长的比值未见组间差异(P>0.05)。心肌层厚度50日龄组显著高于3日龄组、20日龄组和30日龄组(P<0.05),心外膜和心内膜厚度未见日龄差异(P>0.05)。心肌层和心壁胶原纤维含量50日龄组都显著高于3日龄组和20日龄组(P<0.05)。王锦蛇心与吻端的距离与体全长的比值随发育进程无明显变化,在首次蜕皮和主动摄食后,心肌层厚度增厚、胶原纤维含量增多,提示心肌功能逐渐增强。

Age-Dependent Variations in Heart Position, Histological Parameters and Collagen Fiber Content in Farmed King Ratsnake (Elaphe carinata)

Morphological measurements, hematoxylin-eosin staining and Masson staining were employed to determine the age-dependent variations in body size and heart position of the farmed king ratsnakes, Elaphe carinata, under two years old, and in the thickness of epicardial, myocardial, and endocardial layers, andcollagen fiber content in those under fifty days old. All statistical analyses were performed using SPSS software packages (SPSS 19.0 for windows). One-way ANOVA and multiple comparisons were used to compare the differences of body mass (BM), total body length (TBL), ratio of BM to TBL, fatness, heart-to-head distance, and heart position relative to total body length, as well as the thickness of epicardial, myocardial, and endocardial layers, and collagen fiber content among different age groups. Results were presented as means ± standard error, and P < 0.05 was considered to be statistically significant. BM, TBL and the ratio of BM to TBL all showed the highest value in the 2-year old group, secondarily in the 1-year old group, and then dropped significantly in the other age groups (Table1, P < 0.05). However, fatness in the 3-day or 7-10-day old group was significantly higher than that of 1-year or 2-year old group (Table 1, P < 0.05). Heart-to-head distance in the 1-year or 2-year old group was significantly higher than that of any other age group (Table 1, P < 0.05), but heart position relative to total body length showed no significant difference among groups (Table 1, P > 0.05). Within 50 days of postembryonic period, the thickness of myocardial layer was significantly higher in the 50-day old group than that of 3-, 20- or 30-day old group (Table 2, P < 0.05), but no significant differences were found for the thickness of both epicardial and endocardial layers (Table 2, P > 0.05); Collagen fiber content of myocardial layer and heart wall layer in the 50 -day old group was greatly higher than that of 3- or 20-day old group (Table 3, P < 0.05). The relative position of the heart did not change significantly, but the thickness of myocardial layer was greatly increased and more collagen fiber content was observed with the developmental process, suggesting that the heart function of Elaphe carinata is gradually enhanced after the first slough and active feeding.