An efficient regeneration protocol for rapid mass propagation and uptake of heavy metals in Albizia lebbeck (L.), a fast growing, medicinally as well as economically important timber yielding tree was developed. Nodal segments derived
from a 20-year-old tree were cultured on MS (Murashige and Skoog) medium supplemented with 10 μM 6-Benzyladenine (BA) and
1 μM α-Naphthalene acetic acid (NAA) showed optimum shoot regeneration frequency (76.6%), number of shoots (23.2 ± 0.28) per
explant and shoot length (2.86 ± 0.08 cm) after 10 weeks of culture. After standardizing a reliable protocol for micropropagation,
effects of ZnSO4 (0.06–0.48 mM), CuSO4 (0.02–0.2 mM) and CdCl2 (0.0001–0.001 mM) on shoot morphogenesis were also assessed. The regenerated shoots maintained on maintenance medium (MS + 10.0 μM
BA + 1.0 μM NAA) containing ZnSO4 (0.06 mM) showed maximum response in terms of shoot number (24.5 ± 0.83) and length (5.9 ± 0.05 cm) after 10 weeks of culture.
Proline content showed an increasing trend while chlorophyll (a and b) content exhibited decreasing trend with an increased
metal concentrations compared to MM cultures, and maximum increase in proline and decrease in chlorophyll content was recorded
in cultures grown on Cd-enriched medium. Best rooting was accomplished on half strength MS medium with 2.0 μM IBA and ZnSO4 (0.06 mM). The plantlets thus obtained were successfully hardened and transferred to greenhouse with 75% survival rate and
exhibited normal morphological characteristics compared to donor plant. 相似文献
Abnormally high spiking activity can damage neurons. Signaling systems to protect neurons from the consequences of abnormal discharge activity have been postulated. We generated conditional mutant mice that lack expression of the cannabinoid receptor type 1 in principal forebrain neurons but not in adjacent inhibitory interneurons. In mutant mice,the excitotoxin kainic acid (KA) induced excessive seizures in vivo. The threshold to KA-induced neuronal excitation in vitro was severely reduced in hippocampal pyramidal neurons of mutants. KA administration rapidly raised hippocampal levels of anandamide and induced protective mechanisms in wild-type principal hippocampal neurons. These protective mechanisms could not be triggered in mutant mice. The endogenous cannabinoid system thus provides on-demand protection against acute excitotoxicity in central nervous system neurons. 相似文献
Background: It is well known that the development of brain oxidative stress is one of the most serious complications of arterial hypertension that evokes brain tissue damage. The aim of this study was to examine the effects of atorvastatin treatment (20 mg/kg/day), as an antioxidant, to prevent the brain tissue oxidative stress in the hypertensive (HTN) rats. Methods: Experiments were performed in four groups of rats (n = 5 each group): sham, sham-treated, HTN and HTN treated. Rats were made HTN by aortic constriction above the renal arteries. After 30 days, rats were slaughtered under deep anesthesia to remove brain hemispheres. After tissue homogenization, enzyme activities of superoxide dismutase (SOD) and catalase (CAT), as well as glutathione (GSH) content and malondialdehyde (MDA) level were determined by biochemical methods. Results: In HTN rats, arterial blood pressure was increased about 40% and brain enzyme activities of SOD and CAT were significantly decreased compared with sham group. Induction of hypertension significantly decreased GSH content and increased MDA level of brain tissue. Treatment with atorvastatin enhanced the activity of SOD and prevented from GSH decrement during hypertension. Conclusion: Based on the findings of this study, treatment with atorvastatin might have saved the brain tissue of HTN rats from hypertension-induced oxidative stress. Key Words: Atorvastatin, Aortic coarctation, Oxidative stress, Hypertension相似文献
Chilocorus bipustulatus L. (Col.: Coccinellidae) is a predatory coccinellid with a wide geographical distribution. Biological control programs should have a good understanding of the capacity of a predator to kill the target prey. Therefore, the age-stage specific predation rate and functional response of C. bipustulatus feeding on Agonoscena pistaciae (Hem.: Psyllidae) were studied at 18, 25, and 32 °C (65?±?5%RH and 16 L: 8D) to confirm its potential as a biological control agent of common pistachio psylla. The functional response at 18 and 25 °C were described by type II and type III at 32 °C. The estimated maximum attack rate (T/Th) was at 25 °C. Moreover, the highest net feeding (C0) was observed at 25 °C (3271.5 psyllids). This laboratory study, thus, suggested that the predatory coccinellid C. bipustulatus reacted to the rise of temperature by enhancing the predation rate on A. pistaciae.
A highly reproducible and efficient in vitro shoot regeneration system was developed in a potential medicinal plant, Albizia lebbeck using root explants. Root explants from 15 day-old-aseptic seedlings were cultured on Murashige and Skoog (MS) medium supplemented
with different concentrations (0.5, 2.5, 5.0, 7.5 and 10.0 μM) of 6-Benzyladenine (BA), Kinetin (Kn), 2-Isopentenyl adenine
(2-iP) singly as well as in combination with α-Naphthalene acetic acid (NAA) (0.1, 0.5, 1.0, 1.5 and 2.0 μM). The highest
rate of shoot multiplication (16.0 ± 1.87 for the average shoot number and 5.16 ± 0.38 cm for shoot length) was achieved on
MS medium supplemented with 7.5 μM BA and 0.5 μM NAA. The effects of medium type, medium strength, pH and subculture on shoot
induction and proliferation were also tested. An average of 21.6±2.87 shoots per explants could be obtained following this
protocol. Rooting was achieved on microshoots using half strength MS medium with 2.0 μM Indole-3-butyric acid (IBA) after
four weeks of culture. The in vitro raised healthy plantlets were successfully established in earthen pots containing garden soil and grown in greenhouse with
>80% survival rate. 相似文献