OBJECTIVE: To determine the regulation of the expression of NMDA receptor-1 induced by NMDA in the brain of neonatal SD rats. METHODS: Neonatal SD rats (n=90) were randomly divided into normal control (n=6) and NMDA injected group (subdivided into 10 nmol-0 min, 15 min, 30 min, 1 h, 2 h, 4 h groups, and 10, 20, 50 nmol groups, each n=6). NMDA fluorescent inmmunohistological staining and TTC (2,3,5-triphenyltetrazoliun chloride) staining techniques were used. RESULTS: At 30 min after the injection of 10 nmol NMDA, a few NR1 positive cells could be observed along the injection tract. At 1 h after the injection, NR1 positive cells in large quantity could be observed in the hippocampal CA1 region and paraventricular thalamus of the ipsilateral hemisphere. The number and location of positive cells at 2 h and 4 h after the injection were not much different from that at 1 h after the injection. At 2 h after injection, stronger NR1 expression was observed in the 50 nmol injection group. In addition, slight crinkle of the cell wall with mild condensation of the nuclei was also observed in the 50 nmol injection group. At 2 h after the injection, no abnormality was observed in 10, 20, or 50 nmol group after TTC staining. CONCLUSION The NR1 induced by NMDA is expressed in a time-dependent and dose-dependent pattern after a short period of "delay", providing a possible "therapeutic window" for using NMDA receptor antagonist to treat diseases relating to the NMDA receptor activation.
Animals ; Animals, Newborn ; Brain ; metabolism ; Dose-Response Relationship, Drug ; Mice ; N-Methylaspartate ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; biosynthesis ; Time Factors

OBJECTIVETo identify genes expressed in the fetal heart that are potentially important for myocardial development and cardiomyocyte proliferation.

METHODSmRNAs from fetal (29 weeks) and adult cardiomyocytes were use for suppression subtractive hybridization (SSH). Both forward (fetal as tester) and reverse (adult as driver) subtractions were performed. Clones confirmed by dot-blot analysis to be differentially expressed were sequenced and analyzed.

RESULTSDifferential expressions were detected for 39 out of 96 (41%) clones on forward subtraction and 24 out of 80 (30%) clones on reverse. For fetal dominating genes, 28 clones matched to 10 known genes (COL1A2, COL3A1, endomucin, HBG1, HBG2, PCBP2, LOC51144, TGFBI, vinculin and PND), 9 clones to 5 cDNAs of unknown functions (accession AK021715, AF085867, AB040948, AB051460 and AB051512) and 2 clones had homology to hEST sequences. For the reverse subtraction, all clones showed homology to mitochondrial transcripts.

CONCLUSIONSWe successfully applied SSH to detect those genes differentially expressed in fetal cardiac myocytes, some of which have not been shown relative to myocardial development.

Aged ; Cells, Cultured ; Collagen ; Collagen Type I ; Collagen Type III ; genetics ; DNA-Binding Proteins ; genetics ; Forkhead Transcription Factors ; Gene Expression ; physiology ; Heart ; embryology ; growth & development ; Heterogeneous-Nuclear Ribonucleoproteins ; genetics ; Humans ; Nerve Tissue Proteins ; genetics ; Nucleic Acid Hybridization ; RNA-Binding Proteins ; Transcription Factors ; Transforming Growth Factor beta ; genetics ; Transforming Growth Factor beta1 ; Vinculin ; genetics

Objective To study the effect of the body proportion and pubertal growth spurt on the stature of children with β-thalassaemia major.Conclusions An abnormal U:L ratio was commonly observed in patients with β-thalassaemia major and may be one factor contributing to the short stature of these patients. Abnormal puberty was present in a significant proportion of children and the lack of a pubertal growth spurt was found to be detrimental to adult height.