Destructive Changes in the Neuronal Structure of the FVB/N Mouse Retina.

We applied a series of selective antibodies for labeling the various cell types in the mammalian retina. These were used to identify the progressive loss of neurons in the FVB/N mouse, a model of early onset retinal degeneration produced by a mutation in the pde6b gene. The immunocytochemical studies, together with electroretinogram (ERG) recordings, enabled us to examine the time course of the degenerative changes that extended from the photoreceptors to the ganglion cells at the proximal end of the retina.

Potassium channel Kv2.1 is regulated through protein phosphatase-1 in response to increases in synaptic activity.

The functional stability of neurons in the face of large variations in both activity and efficacy of synaptic connections suggests that neurons possess intrinsic negative feedback mechanisms to balance and tune excitability. While NMDA receptors have been established to play an important role in glutamate receptor-dependent plasticity through protein dephosphorylation, the effects of synaptic activation on intrinsic excitability are less well characterized. We show that increases in synaptic activity result in dephosphorylation of the potassium channel subunit Kv2.

Glycinergic feedback enhances synaptic gain in the distal retina.

Glycine input originates with interplexiform cells, a group of neurons situated within the inner retina that transmit signals centrifugally to the distal retina. The effect on visual function of this novel mechanism is largely unknown. Using gramicidin-perforated patch whole cell recordings, intracellular recordings and specific antibody labelling techniques, we examined the effects of the synaptic connections between glycinergic interplexiform cells, photoreceptors and bipolar cells.

Dopamine modulates the off pathway in light-adapted mouse retina.

DL-2-Amino-4-phosphonobutyric acid (APB) is often used as a tool to block On pathways in studies of interactions between On and Off pathways in retinas. APB is an agonist of mGluR6 receptors and hyperpolarizes the On cone bipolar cells and rod bipolar cells. How APB affects Off responses of retinal ganglion cells (RGCs) in mouse retinas under dark and light adaptation is not clear.

Hyaluronan Does Not Affect Bupivacaine's Inhibitory Action on Voltage-Gated Potassium Channel Activities in Bovine Articular Chondrocytes.

Objectives. The objective of this paper is to determine if hyaluronan affects bupivacaine's anesthetic function. Methods.

The roles of ionotropic glutamate receptors along the On and Off signaling pathways in the light-adapted mouse retina.

Although the locations of glutamate receptors along the On and Off pathways have been determined, how these receptors modulate the retinal outputs--the light-evoked and spontaneous activities of individual ganglion cells--is not fully understood in the mouse retina. Specifically, how these receptors mediate On and Off responses of retinal ganglion cells in mouse retina under light adaptation remains unknown. Since mouse retina has become a powerful model for vision research, the functions of glutamate receptors along the On and Off pathways in mouse need to be determined.

Retina protective effect of acidic fibroblast growth factor after canceling its mitogenic activity.

Purpose: The aim of this study was to investigate the effect of mutant of acidic fibroblast growth factor (MaFGF) on N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in Sprague-Dawley rats.

Methods: Fifty (50)-day-old female Sprague-Dawley rats were given a single intraperitoneal injection of normal saline (NS) or 60 mg x kg(-1) body weight of MNU, and then NS or different doses of MaFGF were injected intravitreally twice at 0 and 12 h after NS or MNU treatment. After NS or MNU treatment for different times, the apoptotic index of the photoreceptor cell was detected by TUNEL labeling, whereas the mRNA expressions and the protein levels of antiapoptotic Bcl-2 and proapoptotic Bax were determined by reverse transcriptase polymerase chain reaction and Western blotting, respectively.

Microarray expression analysis of the early N-methy-N-nitrosourea-induced retinal degeneration in rat.

The study was undertaken to investigate the gene expressions in N-methy-N-nitrosourea (MNU)-induced rat retinal degeneration (RD) by performing microarray analysis of retinal RNA at 12h. All rats were randomly divided into a normal group, a 12h model group and a 24h model group. Rats in the two model groups received a single intraperitoneal injection of 40 mg/kg body weight of MNU, while those in the normal group were injected with equivalent volume of physiological saline.

Protective effect of glycyrrhizin, glycyrrhetic acid and matrine on acute cholestasis induced by alpha-naphthyl isothiocyanate in rats.

Alpha-naphthyl isothiocyanate (ANIT) is a known hepatotoxicant that causes acute cholestatic hepatitis characterized by the infiltration of neutrophils around bile ducts and necrotic hepatocytes. The effects of glycyrrhizin (GL), 18beta-glycyrrhetinic acid (GA), matrine (MT), oxymatrine (OMT), salvianolic acid B (SAB), silymarin (SI) and dexamethasone (DEX) on ANIT-induced acute cholestasis in rats were investigated. Serological and histological data demonstrated that the administration of GL, GA or MT all protected against hepatocyte injury and cholestasis induced by ANIT.

Ketoprofen glucuronidation and bile excretion in carbon tetrachloride and alpha-naphthylisothiocyanate induced hepatic injury rats.

A pharmacokinetic study was carried out in rats to investigate the effects of experimental hepatic injury on the liver glucuronidation and bile excretion of ketoprofen (KP) and its glucuronides (KPGs). In vivo, KP (20mg/kg b.w.

[Changes of NF-kappaB/I kappa B alpha in N-methyl-N-nitrosourea-induced retinal damage in rats].

Objective: To observe the changes of nuclear factor-kappa B (NF-kappaB) in the course of N-methyl-N-nitrosourea (MNU)-induced apoptosis of rat retinal photoreceptor cells and investigate the mechanism of MNU-induced retinal damage.

Methods: A single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats, which were sacrificed at different intervals after MNU treatment. The retinal damage was examined with optical microscopy and photoreceptor cell apoptosis detected by TUNEL assay.

[Protective effects of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea and its mechanism].

Aim: To study the protective effect of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley (SD) rats.

Methods: Ligustrazine injections of different doses were injected intraperitoneally into 47-day female SD rats once a day and a single intraperitoneal injection of MNU 60 mg x kg(-1) was given to 50-day rats. At different intervals after MNU treatment,the animals were sacrificed.

N-methyl-N-nitrosourea-induced apoptosis of photoreceptor cells in Sprague-Dawley rats via nuclear factor-kappaB.

Background: Previous studies have showed that photooxidative stress can lead to down-modulation of nuclear factor-kappa B (NF-kappaB) activity causing apoptosis of cultured photoreceptor cells. This study aimed at investigating whether NF-kappaB was involved in photoreceptor cells apoptosis induced by N-methyl-N-nitrosourea (MNU) in rats.

Methods: A single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats.

[Protective effect of non-mitogenic haFGF on retinal injury induced by N-methyl-N-nitrosourea in Sprague-Dawley rats].

Aim: To study the effect of non-mitogenic human acidic fibroblast growth factor (nm-haFGF) on retinal injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley rats and its mechanism.

Methods: Female rats of 50-days-old were injected with MNU (60 mg x kg(-1)) intraperitoneally, and three doses of nm-haFGF (1.25 microg, 2.

Tetramethylpyrazine protected photoreceptor cells of rats by modulating nuclear translocation of NF-kappaB.

Aim: To evaluate the effect of tetramethylpyrazine (TMP) injection on retinal damage induced by N-methyl-N-nitrosourea (MNU) in rats and on nuclear factor-kappa B (NF-kappaB) family members.

Methods: Female Sprague-Dawley (SD) rats were randomly divided into groups: (i), control group; (ii), model group; and (iii), TMP-injection groups, in which the rats were subdivided into 40 mg/kg, 80 mg/kg and 160 mg/kg groups. Drugs were injected ip into 47-day-old SD rats once a day.

[The toxic effect of N-methyl-N- nitrosourea on retina in rats].

Purpose: To observe the toxic effect of N-methyl-N-nitrosourea (MNU) on photoreceptor cells within retina of SD rats.

Methods: At 50 days of age, 100 female rats received a single intraperitoneal injection of MNU at different doses of 50 mg/kg, 60 mg/kg, 70 mg/kg and 80 mg/kg body weight, respectively. Each group had 6 rats and 4 untreated rats were used as normal control.

[Antitumor effect of alcohol extract from Sesamum indicum flower on S180 and H22 experimental tumor].

Objective: To investigate the antineoplasm effect of extract from Sesamum indicum L. flower.

Method: Observing the effects of alcohol extract from Sesamum indicum flower on tumor growth in sarcoma 180 (S180) and Heps 22 (H22) tumorigenic mouse, and on weight of immune organs.

[Apoptosis induced by diacetyldianhydrogalactitol and its mechanism in HL-60 leukemia cells].

Aim: To investigate the apoptosis induced by diacetyldianhydrogalactitol (DADAG) and its mechanism in human HL-60 leukemia cells.

Methods: Inhibition of proliferation was measured by MTT assay. DADAG-induced apoptosis in HL-60 cells was observed by electron microscopy, flow cytometry and DNA fragmentation assay.

Caspases promoted DADAG-induced apoptosis in human leukemia HL-60 cells.

Aim: To investigate the roles of caspases in diacetyldianhydrogalactitol (DADAG)-induced apoptosis in human leukemia HL-60 cells.

Methods: Inhibition of proliferation was measured by MTT assay. DADAG-induced apoptosis in HL-60 cells was observed by electron microscopy, flow cytometry, and DNA fragmentation assay.