Phenylpropanoid Derivatives Are Essential Components of Sporopollenin in Vascular Plants.

The outer wall of pollen and spores, namely the exine, is composed of sporopollenin, which is highly resistant to chemical reagents and enzymes. In this study, we demonstrated that phenylpropanoid pathway derivatives are essential components of sporopollenin in seed plants. Spectral analyses showed that the autofluorescence of Lilium and Arabidopsis sporopollenin is similar to that of lignin. Thioacidolysis and NMR analyses of pollen from Lilium and Cryptomeria further revealed that the sporopollenin of seed plants contains phenylpropanoid derivatives, including p-hydroxybenzoate (p-BA), p-coumarate (p-CA), ferulate (FA), and lignin guaiacyl (G) units. The phenylpropanoid pathway is expressed in the tapetum in Arabidopsis, consistent with the fact that the sporopollenin precursor originates from the tapetum. Further germination and comet assays showed that this pathway plays an important role in protection of pollen against UV radiation. In the pteridophyte plant species Ophioglossum vulgatum and Lycopodium clavata, phenylpropanoid derivatives including p-BA and p-CA were also detected, but G units were not. Taken together, our results indicate that phenylpropanoid derivatives are essential for sporopollenin synthesis in vascular plants. In addition, sporopollenin autofluorescence spectra of bryophytes, such as Physcomitrella and Haplocladium, exhibit distinct characteristics compared with those of vascular plants, indicating the diversity of sporopollenin among land plants.

[Changes of the microcirculatory blood perfusion at "Feishu" (BL 13) in the COPD rats].

OBJECTIVE: To observe the change of the specificity of the microcirculatory blood perfusion at the area of "Feishu" (BL 13) in the rats of chronic obstructive pulmonary disease (COPD). METHODS: According to the random number table, 60 Wistar rats were divided into a 29 d model No. 1 group (C1 group), a 29 d normal control No.1 group (N1 group), a 89 d model No.2 group (C2 group) and a 89 d normal control No. 2 group (N2 group), 15 rats in each one. In the C1 and C2 groups, the smoking and intratracheal drops of endotoxin were used in combination to prepare COPD model. The rats were fed normally in the N1 and N2 groups. "Feishu" (BL 13), "Xinshu" (BL 15), the lateral site of "Feishu" (BL 13) and the lateral site of "Xinshu" (BL 15) were selected as the monitoring points. The pericam perfusion speckle imager (PeriCam PSI System) was adopted to monitor the microcirculatory perfusion unit (PU) at the monitoring points before and in 29 d and 89 d after modeling separately. RESULTS: Before modeling, the differences in PU were not significant at each monitoring point in comparison among the 4 groups and the differences were not significant among "Feishu" (BL 13) and "Xinshu" (BL 15) as well as their lateral sites (all P>0.05). After modeling, PU was increased at each monitoring point in the C1 and C2 groups (all P<0.05). PU in the C1 group was higher than the N1 group and that in the C2 group was lower than the N2 group, PU at each monitoring point in the C1 group were higher than the C2 group, indicating the significant differences (all P<0.05). In the C1 and C2 groups, the specific change occurred, in which PU at "Feishu" (BL 13) was higher than its lateral site. But such specific change did not happen in the N1 and N2 groups. CONCLUSION: PU at "Feishu" (BL 13) presents the specific change relevant with the sickness duration in the COPD rats.