Northern blot analysis of glutathione S-transferase (GST) Yb1 mRNA in different tissues of male and female rats revealed that its tissue-specific transcription patterns were highly sex hormone related. Although the GS...Northern blot analysis of glutathione S-transferase (GST) Yb1 mRNA in different tissues of male and female rats revealed that its tissue-specific transcription patterns were highly sex hormone related. Although the GST Yb1 mRNA could be detected in most of the tissues examined at various levels, the highest abundance was observed in the ventral prostate, uterus and liver, which were the main target tissue for androgen, estrogen and glucocorticoid respectively The effect of androgen on the transcription of GST Yb1 was also tissue-specific. Since androgen withdrawal by castration caused the up-regulation of GST Yb1 mRNA in the ventral prostate but down-regulation in the liver and no effect in the brain, evaluation of this system for studying the regulation mechanisms of gene expression by which androgen exerts its differential effects has been discussed.展开更多
The nature of brain interstitial fluid （ISF） has long been a subject of controversy. Most of the previous studies on brain ISF were carded out in vitro. In the present study, a novel method was developed to characte...The nature of brain interstitial fluid （ISF） has long been a subject of controversy. Most of the previous studies on brain ISF were carded out in vitro. In the present study, a novel method was developed to characterize ISF in the living rat brain by magnetic resonance （MR） imaging using gadolinium-diethylenetriaminepentaacetic acid （Gd-DTPA） as a tracer. Sprague Dawley rats （n=8） were subjected to MR scanning before and after the introduction of Gd-DTPA into the caudate nucleus. A one-way drainage of brain ISF was demonstrated on the dynamic MR images. According to the traditional diffusion model, the diffusion and clearance rate constants of the tracer within brain extracellular space （ECS） were derived as （3.38±1.07）×10^-4 mm2 s^-1 and （7.60±4.18）×10^-5 s^-1. Both diffusion and bulk flow contributed to the drainage of ISF from the caudate nucleus, which demonstrated an ISF-cerebrospinal fluid confluence in the subarachnoid space at the lateral and ventral surface of the brain cortex at 3 h after the injection. By using this newly developed method, the brain ECS and ISF can be quantitatively measured simultaneously in the living brain, which will enhance the understanding of ISF and improve the efficiency of drug therapy via the brain interstitium.展开更多
文摘Northern blot analysis of glutathione S-transferase (GST) Yb1 mRNA in different tissues of male and female rats revealed that its tissue-specific transcription patterns were highly sex hormone related. Although the GST Yb1 mRNA could be detected in most of the tissues examined at various levels, the highest abundance was observed in the ventral prostate, uterus and liver, which were the main target tissue for androgen, estrogen and glucocorticoid respectively The effect of androgen on the transcription of GST Yb1 was also tissue-specific. Since androgen withdrawal by castration caused the up-regulation of GST Yb1 mRNA in the ventral prostate but down-regulation in the liver and no effect in the brain, evaluation of this system for studying the regulation mechanisms of gene expression by which androgen exerts its differential effects has been discussed.
基金supported by the National Natural Science Foundation of China (Grant Nos. 30972811, 81171080 and 81071148)the Twelfth Five-year Plan for National Science and Technology of China (Grant No.2012BAI15B009)
文摘The nature of brain interstitial fluid （ISF） has long been a subject of controversy. Most of the previous studies on brain ISF were carded out in vitro. In the present study, a novel method was developed to characterize ISF in the living rat brain by magnetic resonance （MR） imaging using gadolinium-diethylenetriaminepentaacetic acid （Gd-DTPA） as a tracer. Sprague Dawley rats （n=8） were subjected to MR scanning before and after the introduction of Gd-DTPA into the caudate nucleus. A one-way drainage of brain ISF was demonstrated on the dynamic MR images. According to the traditional diffusion model, the diffusion and clearance rate constants of the tracer within brain extracellular space （ECS） were derived as （3.38±1.07）×10^-4 mm2 s^-1 and （7.60±4.18）×10^-5 s^-1. Both diffusion and bulk flow contributed to the drainage of ISF from the caudate nucleus, which demonstrated an ISF-cerebrospinal fluid confluence in the subarachnoid space at the lateral and ventral surface of the brain cortex at 3 h after the injection. By using this newly developed method, the brain ECS and ISF can be quantitatively measured simultaneously in the living brain, which will enhance the understanding of ISF and improve the efficiency of drug therapy via the brain interstitium.
