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131.
目的:研究17-丙烯胺-17去甲氧格尔德霉素(17-Allylamino-17-emethoxy-geldanamycin, 17-AAG)对球囊损伤后大鼠颈总动脉内膜增生的影响及可能作用机制。方法:将清洁级雄性SD大鼠36只按照随机数字法分为假手术组(Sham组)12只、球囊损伤组(Balloon injury, BI组)12只及17-AAG治疗组(17-AAG组)12只。采用2F Fogarty球囊建立大鼠颈总动脉球囊损伤组模型,17-AAG治疗组大鼠在建模后腹腔注射17-AGG(20 mg/kg 2d)。各组大鼠于球囊损伤3周后取损伤段颈总动脉,通过HE染色观察血管内膜形态学改变并评估内膜增生情况,免疫组化染色(Immunohistochemical staining,IHS)法检测血管壁增殖细胞核抗原(Proliferating cell nuclear antigen,PCNA)的表达,评估血管平滑肌细胞的增殖情况。流式细胞术检测血管平滑肌细胞的凋亡情况。结果:BI组、17-AAG组大鼠球囊损伤后颈总动脉内膜出现不同程度增生,内膜/中膜面积比(Intima area/Membrane area,I/M)均较Sham组显著升高(P0.05);17-AAG组的I/M较BI组明显下降(P0.05)。BI组、17-AAG组颈总动脉PCNA表达水平较Sham组明显升高(P0.05),较BI组显著降低(P0.05)。BI组、17-AAG组大鼠血管平滑肌细胞凋亡率较Sham组显著升高(P0.05);17-AAG组大鼠血管平滑肌细胞凋亡程度较BI组明显升高(P0.05)。结论:17-AAG对球囊损伤后颈总动脉内膜增生存在抑制作用,其机制可能是通过提高血管平滑肌细胞凋亡率影响其增殖程度。 相似文献
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Evans DJ 《Developmental biology》2003,256(1):114-126
The traditional view that all parts of the ribs originate from the sclerotome of the thoracic somites has recently been challenged by an alternative view suggesting that only the proximal rib derives from the sclerotome, while the distal rib arises from regions of the dermomyotome. In view of this continuing controversy and to learn more about the cell interactions during rib morphogenesis, this study aimed to reveal the precise contributions made by somitic cells to the ribs and associated tissues of the thoracic cage. A replication-deficient lacZ-encoding retrovirus was utilized to label cell populations within distinct regions of somites 19-26 in stage 13-18 chick embryos. Analysis of the subsequent contributions made by these cells revealed that the thoracic somites are the sole source of cells for the ribs. More precisely, it is the sclerotome compartment of the somites that contributes cells to both the proximal and distal elements of the ribs, confirming the traditional view of the origin of the ribs. Results also indicate that the precursor cells of the ribs and intercostal muscles are intimately associated within the somite, a relationship that may be essential for proper rib morphogenesis. Finally, the data from this study also show that the distal ribs are largely subject to resegmentation, although cell mixing may occur at the most sternal extremities. 相似文献
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The perivertebral musculature of lizards is critical for the stabilization and the mobilization of the trunk during locomotion. Some trunk muscles are also involved in ventilation. This dual function of trunk muscles in locomotion and ventilation leads to a biomechanical conflict in many lizards and constrains their ability to breathe while running (“axial constraint”) which likely is reflected by their high anaerobic scope. Furthermore, different foraging and predator‐escape strategies were shown to correlate with the metabolic profile of locomotor muscles in lizards. Because knowledge of muscle's fiber‐type composition may help to reveal a muscle's functional properties, we investigated the distribution pattern of muscle fiber types in the perivertebral musculature in two small lizard species with a generalized body shape and subjected to the axial constraint (Dipsosaurus dorsalis, Acanthodactylus maculatus) and one species that circumvents the axial constraint by means of gular pumping (Varanus exanthematicus). Additionally, these species differ in their predator‐escape and foraging behaviors. Using refined enzyme‐histochemical protocols, muscle fiber types were differentiated in serial cross‐sections through the trunk, maintaining the anatomical relationships between the skeleton and the musculature. The fiber composition in Dipsosaurus and Acanthodactylus showed a highly glycolytic profile, consistent with their intermittent locomotor style and reliance on anaerobic metabolism during activity. Because early representatives of diapsids resemble these two species in several postcranial characters, we suggest that this glycolytic profile represents the plesiomorphic condition for diapsids. In Varanus, we found a high proportion of oxidative fibers in all muscles, which is in accordance with its high aerobic scope and capability of sustained locomotion. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
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Ki-Sung Kim Yuichiro Arima Taro Kitazawa Koichi Nishiyama Rieko Asai Yasunobu Uchijima Takahiro Sato Giovanni Levi Sachiko Kitanaka Takashi Igarashi Yukiko Kurihara Hiroki Kurihara 《Mechanisms of development》2013,130(11-12):553-566
Endothelin-1 (Edn1), originally identified as a vasoconstrictor peptide, is involved in the development of cranial/cardiac neural crest-derived tissues and organs. In craniofacial development, Edn1 binds to Endothelin type-A receptor (Ednra) to induce homeobox genes Dlx5/Dlx6 and determines the mandibular identity in the first pharyngeal arch. However, it remains unsolved whether this pathway is also critical for pharyngeal arch artery development to form thoracic arteries. Here, we show that the Edn1/Ednra signaling is involved in pharyngeal artery development by controlling the fate of neural crest cells through a Dlx5/Dlx6-independent mechanism. Edn1 and Ednra knock-out mice demonstrate abnormalities in pharyngeal arch artery patterning, which include persistent first and second pharyngeal arteries, resulting in additional branches from common carotid arteries. Neural crest cell labeling with Wnt1-Cre transgene and immunostaining for smooth muscle cell markers revealed that neural crest cells abnormally differentiate into smooth muscle cells at the first and second pharyngeal arteries of Ednra knock-out embryos. By contrast, Dlx5/Dlx6 knockout little affect the development of pharyngeal arch arteries and coronary arteries, the latter of which is also contributed by neural crest cells through an Edn-dependent mechanism. These findings indicate that the Edn1/Ednra signaling regulates neural crest differentiation to ensure the proper patterning of pharyngeal arch arteries, which is independent of the regional identification of the pharyngeal arches along the dorsoventral axis mediated by Dlx5/Dlx6. 相似文献