In this study we tested the hypotheses that root classes would exhibit distinctive anatomical and architectural responses to drought stress, and that those responses would vary along the root axes. The root systems of four maize (Zea mays L.) sweet corn genotypes designated SC1, SC2, SC3 and SC4 were phenotyped under well-watered and drought treatments in greenhouse mesocosms, permitting increasing stratification of moisture availability as the drought progressed. Anatomical and architectural responses to drought were evaluated for each root class. Lignin distribution was assessed by image processing of UV-illuminated root cross-sections acquired by laser ablation tomography. The two cultivars with less biomass reduction under drought, SC3 and SC4, substantially enhanced lateral root development along the apical segments of axial roots when plants were grown with drought stress. These segments grew into the deeper part of the mesocosm where more moisture was available. Apical segments of the axial and large lateral roots from drought-stressed plants were thicker and had greater theoretical axial water conductance than basal segments, especially in SC3 and SC4. Basal segments of crown roots of SC3 and SC4 showed increased lignification of the stele under drought. Root anatomical and architectural responses to drought are complex and vary among cultivars and root classes, and along root axes. Drought-induced proliferation of lateral roots on apical segments of axial roots would be expected to enhance deep water acquisition, while lignification of axial roots could help preserve axial water transport.
The therapeutic effects of melatonin or vitamin E plus Se (vE + Se) on the restrain of the heroin withdrawal-induced oxidative
stress were studied. For this, rats were divided into ten groups. The rats were injected by fixed or variable doses of heroin
for 16 consecutive days, and naloxone was given 1 h after the last heroin injection. One hour after naloxone administration,
some groups were treated with melatonin or vE + Se. After 1 h this, blood samples were taken, and the levels of malondialdehyde
(MDA) and reduced glutathione (GSH) in whole blood, ascorbic acid, α-tocopherol, retinol, β-carotene, nitrite, nitrate, and
ceruloplasmin levels in the serum were measured. Our findings showed that, naloxone administration precipitated the heroin
withdrawal. This also increased the level of MDA and decreased the levels of GSH in blood. Melatonin or vE + Se administration
prevented the rise in MDA levels and increased the GSH levels. On the other hand, there were some significant differences
between α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels of experimental groups. Results of present
study showed that heroin withdrawal increased the lipid peroxidation and depressed endogenous antioxidative systems. Additionally,
melatonin or vE + Se administrations prevented lipid peroxidation and augmented endogenous antioxidant defense systems. 相似文献
Molecular and Cellular Biochemistry - Arbutin is one of the active ingredients employed in cosmetics as a skin whitening agent. In the present study, the possible effects of arbutin on breast... 相似文献
Heroin use, withdrawal syndrome, and heroin-related deaths are still the most serious public health problems. Antioxidants
and bio-elements are essential for metabolism in living organisms. To our knowledge, there are no data about the effect of
antioxidant therapy on the levels of bio-elements and antioxidant enzymes in the naloxone (NX)-induced heroin withdrawal syndrome.
Therefore, in the present study for the first time, we have investigated the role of antioxidant therapy, melatonin, and vitamin
E plus Se, on the trace and major elements and antioxidant enzymes in the heroin addiction or heroin withdrawal in rats. Glutathione
peroxidase levels were increased and catalase levels were decreased in the all study groups when compared to the sham group.
The level of superoxide dismutase (SOD) in the fixed dose of heroin (FDH) given group was lower; however, in the variable
doses of heroin (VDH) given group SOD level was higher. Furthermore, in withdrawal syndrome, Fe, Mg, Mn, and Ti levels were
diminished and Al, Ca, and Cu levels were increased in the FDH+NX group. Moreover, Mg, Mn, and Se levels were also diminished
and Al level was increased in the VDH+NX group. In conclusion, our results obviously indicated that heroin effected both bio-element
status and antioxidant enzyme activities and, exogenous melatonin or vE+Se therapy might relieve on the element and antioxidant
enzyme the destructive activity caused by heroin. 相似文献