AIM:To investigate the distribution and neurochemical phenotype of endomorphin-2(EM-2)-containing neurons in the submucosal plexus of the rat colon.METHODS:The mid-colons between the right and left flexures were remov...AIM:To investigate the distribution and neurochemical phenotype of endomorphin-2(EM-2)-containing neurons in the submucosal plexus of the rat colon.METHODS:The mid-colons between the right and left flexures were removed from rats,and transferred into Kreb's solution. For whole-mount preparations,the mucosal,outer longitudinal muscle and inner circularmuscle layers of the tissues were separated from the submucosal layer attached to the submucosal plexus. The whole-mount preparations from each rat mid-colon were mounted onto seven gelatin-coated glass slides,and processed for immunofluorescence histochemical double-staining of EM-2 with calcitonin gene-related peptide(CGRP),choline acetyltransferase(Ch AT),nitric oxide synthetase(NOS),neuron-specific enolase(NSE),substance P(SP) and vasoactive intestinal peptide(VIP). After staining,all the fluorescence-labeled sections were observed with a confocal laser scanning microscope. To estimate the extent of the co-localization of EM-2 with CGRP,Ch AT,NOS,NSE,SP and VIP,ganglia,which have a clear boundary and neuronal cell outline,were randomly selected from each specimen for this analysis. RESULTS:In the submucosal plexus of the mid-colon,many EM-2-immunoreactive(IR) and NSE-IR neuronal cell bodies were found in the submucosal plexus of the rat mid-colon. Approximately 6 ± 4.2 EM-2-IR neurons aggregated within each ganglion and a few EM-2-IR neurons were also found outside the ganglia. The EM-2-IR neurons were also immunopositive for Ch AT,SP,VIP or NOS. EM-2-IR nerve fibers coursed near Ch AT-IR neurons,and some of these fibers were even distributed around Ch AT-IR neuronal cell bodies. Some EM-2-IR neuronal cell bodies were surrounded by SP-IR nerve fibers,but many long processes connecting adjacent ganglia were negative for EM-2 immunostaining. Long VIP-IR processes with many branches coursed through the ganglia and surrounded the EM-2-IR neurons. The percentages of the EM-2-IR neurons that were also positive for Ch AT,SP,VIP or NOS were approximately 91% ± 2.6%,36% ± 2.4%,44% ± 2.5% and 44% ± 4.7%,respectively,but EM-2 did not co-localize with CGRP. CONCLUSION:EM-2-IR neurons are present in the submucosal plexus of the rat colon and express distinct neurochemical markers.展开更多
A series of analogs of endomorphin-2 (EM-2) with phenylglycine (Phg) in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance (ESI-Fr-ICR) MS/MS spectra of these ...A series of analogs of endomorphin-2 (EM-2) with phenylglycine (Phg) in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance (ESI-Fr-ICR) MS/MS spectra of these compounds, some b, y, a, and internal ions were observed and slight mass differences between the calculated and observed results are obtained. Their sequences were derived successfully. However, the MS/MS patterns of these analogs with Dphg and Lphg were very similar. It is hard to distinguish them by MS/MS spectra. Moreover, if the third position was substituted by phenylglycine (L or D), a rearrangement could occur in MS/MS experiment to lose proline residue.展开更多
芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛...芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛选法(磁珠-SELEX)开展10轮筛选,经由高通量测序获得6条候补序列(S1~S6),并进行家族性、同源性分析及二级结构预测。结果表明,6条候选核酸适体的重复率可达46.38%,其自由能在-9.02到-2.47 kcal·moL^(-1)之间,根据自由能能量稳定原则,S1和S5吉布斯自由能最低最稳定,分别为-6.70和-9.02 kcal·moL^(-1)。利用ELISA试验进行亲和力测试,结果表明核酸适体S1和S2的亲和能力较强,S1:KD=67.02 nmol·L^(-1),R2=0.925 8,S2:KD=97.65 nmol·L^(-1),R2=0.795 1。核酸适体S1与过敏原Ses i 2的结合力和其他过敏原蛋白相比有显著差异,可视为具有特异性。本研究最终获得一条兼具良好亲和力和特异性的核酸适体S1,为芝麻过敏原快速检测提供了技术支撑。展开更多
基金Supported by Grants from the National Natural Science Foundation of China,No.30971123 and No.81371239
文摘AIM:To investigate the distribution and neurochemical phenotype of endomorphin-2(EM-2)-containing neurons in the submucosal plexus of the rat colon.METHODS:The mid-colons between the right and left flexures were removed from rats,and transferred into Kreb's solution. For whole-mount preparations,the mucosal,outer longitudinal muscle and inner circularmuscle layers of the tissues were separated from the submucosal layer attached to the submucosal plexus. The whole-mount preparations from each rat mid-colon were mounted onto seven gelatin-coated glass slides,and processed for immunofluorescence histochemical double-staining of EM-2 with calcitonin gene-related peptide(CGRP),choline acetyltransferase(Ch AT),nitric oxide synthetase(NOS),neuron-specific enolase(NSE),substance P(SP) and vasoactive intestinal peptide(VIP). After staining,all the fluorescence-labeled sections were observed with a confocal laser scanning microscope. To estimate the extent of the co-localization of EM-2 with CGRP,Ch AT,NOS,NSE,SP and VIP,ganglia,which have a clear boundary and neuronal cell outline,were randomly selected from each specimen for this analysis. RESULTS:In the submucosal plexus of the mid-colon,many EM-2-immunoreactive(IR) and NSE-IR neuronal cell bodies were found in the submucosal plexus of the rat mid-colon. Approximately 6 ± 4.2 EM-2-IR neurons aggregated within each ganglion and a few EM-2-IR neurons were also found outside the ganglia. The EM-2-IR neurons were also immunopositive for Ch AT,SP,VIP or NOS. EM-2-IR nerve fibers coursed near Ch AT-IR neurons,and some of these fibers were even distributed around Ch AT-IR neuronal cell bodies. Some EM-2-IR neuronal cell bodies were surrounded by SP-IR nerve fibers,but many long processes connecting adjacent ganglia were negative for EM-2 immunostaining. Long VIP-IR processes with many branches coursed through the ganglia and surrounded the EM-2-IR neurons. The percentages of the EM-2-IR neurons that were also positive for Ch AT,SP,VIP or NOS were approximately 91% ± 2.6%,36% ± 2.4%,44% ± 2.5% and 44% ± 4.7%,respectively,but EM-2 did not co-localize with CGRP. CONCLUSION:EM-2-IR neurons are present in the submucosal plexus of the rat colon and express distinct neurochemical markers.
文摘A series of analogs of endomorphin-2 (EM-2) with phenylglycine (Phg) in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance (ESI-Fr-ICR) MS/MS spectra of these compounds, some b, y, a, and internal ions were observed and slight mass differences between the calculated and observed results are obtained. Their sequences were derived successfully. However, the MS/MS patterns of these analogs with Dphg and Lphg were very similar. It is hard to distinguish them by MS/MS spectra. Moreover, if the third position was substituted by phenylglycine (L or D), a rearrangement could occur in MS/MS experiment to lose proline residue.
文摘芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛选法(磁珠-SELEX)开展10轮筛选,经由高通量测序获得6条候补序列(S1~S6),并进行家族性、同源性分析及二级结构预测。结果表明,6条候选核酸适体的重复率可达46.38%,其自由能在-9.02到-2.47 kcal·moL^(-1)之间,根据自由能能量稳定原则,S1和S5吉布斯自由能最低最稳定,分别为-6.70和-9.02 kcal·moL^(-1)。利用ELISA试验进行亲和力测试,结果表明核酸适体S1和S2的亲和能力较强,S1:KD=67.02 nmol·L^(-1),R2=0.925 8,S2:KD=97.65 nmol·L^(-1),R2=0.795 1。核酸适体S1与过敏原Ses i 2的结合力和其他过敏原蛋白相比有显著差异,可视为具有特异性。本研究最终获得一条兼具良好亲和力和特异性的核酸适体S1,为芝麻过敏原快速检测提供了技术支撑。