正常中国人中枢运动系统传导时间的测定

本文应用高电压、低输出阻抗刺激器,经皮给予大脑皮层和脊髓电刺激(BSPES),同时在上肢鱼际(Thenar)和下肢胫骨前肌(Muscle tibialis anterior)上记录诱发肌肉动作电位,测定了64名正常健康中国人(男:46;女:18)的中枢运动系统传导时间。受试者年龄为20—67岁,身高为156—185cm。刺激大脑皮层出现反应的潜伏期与刺激脊髓出现反应的潜伏期之差为中枢运动传导时间(CMCT)。实验测得鱼际的 CMCT 为6.69±1.48ms;胫骨前肌的 CMCT 为12.90±1.59ms。经统计学处理证明,CMCT 与左右侧肢体、性别、年龄及身高无关。说明 CMCT 是无损伤测定与评价中枢运动系统功能的较精确的一种客观指标。本文根据所测数据,计算出脊髓内运动传导速度为71.34±10.89 m/s,与文献报道的锥体束传导速度50—70 m/s 相近。因此,CMCT 反映了锥体束的传导时间。     

Embryonic cholinesterase activity during morphogenesis of the mouse genital tract

Summary In the genital tract of male and female mouse embryos cholinesterase activity is described that is independent from innervation. The enzyme activity is localized in the mesenchyme at the junction of Wolffian and Müllerian ducts with the urogenital sinus. During male development prostate buds and vesicular glands grow out into the cholinesterase-active mesenchyme. During female development the active mesenchyme participates in the downgrowth of the vaginal anlage. Ultrastructurally the cholinesterase activity is localized in the perinuclear cisterna and in smooth endoplasmic reticulum of the mesenchymal cells. The enzyme activity disappears with definitive differentiation of the tissue. The embryonic cholinesterase is a component of a primitive muscarinic system. Its relation to the morphogenetic action of testosterone and its possible general functions are discussed.     

Distribution and characterization of the opioid octapeptide met5-enkephalin-arg6-gly7-leu8 in the gastrointestinal tract of the rat

Summary The distribution and characterization of the opioid octapeptide met⁵-enkephalin-arg⁶-gly⁷-leu⁸ (met⁵-enk-arg⁶-gly⁷-leu⁸) within the gastrointestinal tract of the rat has been determined by immunohistochemistry and radioimmunoassay by use of a newly developed antibody to met⁵-enk-arg⁶-gly⁷-leu⁸. With both techniques, met⁵-enk-arg⁶-gly⁷-leu⁸-immunoreactivity (met⁵-enk-arg⁶-gly⁷-leu⁸IR) was detected in all regions of the gastrointestinal (GI) tract except the esophagus. The highest concentration of immunoreactive met⁵-enk-arg⁶-gly⁷-leu⁸ was observed in the colon, while intermediate concentrations were found in the stomach, duodenum, jejunum, and ileum. Immunostained somata were observed chiefly in the myenteric plexus; immunostained processes were present primarily in the myenteric plexus and the circular muscle layer. This distribution pattern is similar to that previously observed with antiserum to met⁵-enkephalin-arg⁶-phe⁷ (met⁵-enk-arg⁶phe⁷). Chromatographic analysis of met⁵-enk-arg⁶-gly⁷leu⁸-immunoreactive peptides extracted from the GI tract revealed the presence of an immunoreactive peptide of high molecular weight which accounted for approximately three-quarters of met⁵-enk-arg⁶-gly⁷-leu⁸-IR in both stomach and colon. These findings suggest a role for peptides related to the octapeptide met⁵-enk-arg⁶-gly⁷-leu⁸ in the regulation of GI function.     

Substance P and enkephalin in transected axons of medulla and spinal cord

The accumulation of transported materials in cut axons is demonstrated by the light and electron microscopic immunocytochemical localization of substance P and enkephalin in the caudal medulla and cervical spinal cord of adult rat. Two days following unilateral knife-cuts in the caudal medulla or spinal (C2-C3) levels, substance P and enkephalin-like immunoreactivity (SPLI and ELI) are detected in lesioned axons located rostral and caudal to the transection. Rostrally, SPLI and ELI are detected in the lateral reticular region and ventrolateral fasciculus corresponding to the location of previously identified bulbospinal pathways. Caudally, previously unidentified, propriospinal pathways showing SPLI are detected in the dorsal columns and in the dorsolateral fasciculus. In contrast, ELI is found caudal to the transection only in the reticular region of the medulla. For both peptides, immunoreactivity is present throughout axons containing numerous large, dense core, and small clear vesicles. These results support the concept of both particulate and soluble modes of transport for substance P and enkephalin within axons of the central nervous system.     

Ontogeny of vasoactive intestinal peptide in the human fetal digestive tract

Immunocytochemistry and radioimmunoassay were used to assess the appearance time and tissue distribution of vasoactive intestinal peptide (VIP) in the digestive tract of the human fetus. By radioimmunoassay, VIP was measurable from 10 weeks of gestation. The peptide was abundantly distributed in the jejuno-ileum and colon, where the tissue peptide concentration rose from 9-14 weeks of gestation (18.4 +/- 4.4 and 22.0 +/- 5.0 pmol/g wet weight, respectively) to 15-21 weeks (83.0 +/- 21.1 and 98.6 +/- 36.4 pmol/g, respectively). Lower concentrations were recorded in pancreas from 9-14 weeks of gestation (4.3 +/- 0.8 pmol/g) to 15-21 weeks (13.9 +/- 3.7 pmol/g). The peptide concentration was 15.6 +/- 1.9 pmol/g in fundus and 25.5 +/- 3.2 pmol/g in antrum from 15 to 21 weeks of gestation. The highest concentration was recorded in duodenum from 15 to 21 weeks of gestation (118.4 +/- 40.8 pmol/g wet weight). Tissue VIP concentration and age were positively correlated in the jejuno-ileum. By immunofluorescence, immunoreactive VIP was localized in nervous fibers in the muscularis externa, in the submucosa and in the lamina propria. Scarce cell bodies were also found in the myenteric plexus. No immunofluorescent endocrine cells were observed. These results suggest: (1) the early appearance of immunoreactive VIP in gut, as early as 10 weeks of gestation; (2) the peptide, localized in nervous structures only, follows the same distribution pattern as that in adults; (3) the development of VIPergic structures is a continuous process, initiated during the 3rd month of pregnancy.     

烧伤后大鼠肠道菌群的改变及其易位

本文报告了25％烧伤后注射免疫抑制剂(地寨米松磷酸钠)大鼠7种肠道细菌的定量、内脏及血液的细菌培养和肠壁的病理形态学改变。单纯烧伤组(B组)和单纯注射免疫抑制剂组(Ⅰ组)动物肠壁的病理改变较轻,肠道菌群改变不明显,其肠道细菌易位率也很低。烧伤后注射免疫抑制剂的动物(BⅠ组)肠壁病变严重,肠道菌群改变明显。其中,肠杆菌在回肠、盲肠,结肠内容物中的菌量均明显升高;回肠内容物中拟杆菌的菌量明显减少;该组动物肠道细菌易位率也明显增高,达60％。此外,BⅠ组、Ⅰ组部分动物发生了由棒状杆菌及由棒状扦菌和肠杆菌混合引起的内源性感染。根据不同肠段肠壁病变严重程度、菌群变化的部位以及不同部位肠管生理功能的不同,我们推测,回肠以上肠段是肠道细菌易位的主要部位。     

Direct and indirect evidence for polypeptide absorption by the teleost gastrointestinal tract

The ability of the gastrointestinal tract of chinook salmon, Oncorhynchus tshawytscha , to absorb polypeptides in vivo was investigated by reference to the appearance of orally administered adrenocorticotropic hormone (ACTH) within the blood of fish previously treated with dexamethasone (3μg g^−l body weight) in order to suppress endogenous ACTH secretion. Further, since cortisol presence within plasma is dependent upon the availability of ACTH, dexamethasone blockade of endogenous ACTH secretion, in conjunction with subsequent measurements of plasma cortisol levels, provides a means by which biological patency of absorbed exogenous ACTH may be demonstrated. Levels of ACTH and cortisol in plasma of dexamethasone-treated salmon were therefore measured for a period of 360 min immediately following oral intubation of ACTH (15μg g⁻¹ body weight). Peak plasma presence of ACTH-like immunoreactivity (676.6 ± 33.6 pg ml⁻¹ plasma) and cortisol (227.1 ± 29.0 ng ml⁻¹ plasma) were recorded 120 min after ACTH administration. Results from the experimental groups were compared to those of 15 control treatments. Since administration of ACTH to chinook salmon elicited a consistent and significant elevation in not only plasma ACTH but also cortisol presence, it is contended that the salmonid gut expresses an ability to absorb polypeptides of dietary origin. The significance of these findings with respect to the oral administration of biologically active peptides and proteins to fish of importance to aquaculture is discussed.     

大熊猫的组织学研究 Ⅲ.消化道显微结构的年龄变化

观察了初生、幼仔、亚成体和老年大熊猫的食管、胃和肠的石蜡切片。与成体的对比,生长发育阶段的主要变化发生在两个主要机能层:粘膜层和肌肉层;衰老的变化则主要出现在粘膜层,尤其是上皮组织的变化最显著,内分泌亲银细胞的数量在生长期似略有增多,成年到老年数量变化不明显。     

Immunochemical study of galanin in the cat digestive tract and autonomic ganglia

The presence of galanin was examined in the cat gut and related autonomic nervous structures using radioimmunoassay (RIA) and high performance liquid chromatography (HPLC). In the gut wall, the concentration of galanin-like immunoreactivity (GAL-LI) was assayed separately in the muscular layers with the nervous plexuses and in the mucosa and ranged from 0.35 to 0.55 pmol/g wet tissue. In the autonomic nervous structures, GAL-LI concentrations ranged from 0.22 (thoracic spinal ganglia) to 0.81 (inferior mesenteric ganglion) pmol/g wet tissue. The presence of galanin was checked by HPLC in the antrum, intestine, and colon. HPLC of extractable material revealed a major peak coeluting with the synthetic porcine peptide and minor earlier peaks representing likely different molecular forms of galanin. Our study strengthens the notion that galanin acts in nervous control of the cat gut functions.