Decreased Immunoreactivities and Functions of the Chloride Transporters, KCC2 and NKCC1, in the Lateral Superior Olive Neurons of Circling Mice

OBJECTIVES: We tested the possibility of differential expression and function of the potassium-chloride (KCC2) and sodium-potassium-2 chloride (NKCC1) co-transporters in the lateral superior olive (LSO) of heterozygous (+/cir) or homozygous (cir/cir) mice. METHODS: Mice pups aged from postnatal (P) day 9 to 16 were used. Tails from mice were cut for DNA typing. For Immunohistochemical analysis, rabbit polyclonal anti-KCC2 or rabbit polyclonal anti-NKCC1 was used and the density of immunolabelings was evaluated using the NIH image program. For functional analysis, whole cell voltage clamp technique was used in brain stem slices and the changes of reversal potentials were evaluated at various membrane potentials. RESULTS: Immunohistochemical analysis revealed both KCC2 and NKCC1 immunoreactivities were more prominent in heterozygous (+/cir) than homozygous (cir/cir) mice on P day 16. In P9-P12 heterozygous (+/cir) mice, the reversal potential (Egly) of glycine-induced currents was shifted to a more negative potential by 50 microM bumetanide, a known NKCC1 blocker, and the negatively shifted Egly was restored by additional application of 1 mM furosemide, a KCC2 blocker (-58.9+/-2.6 mV to -66.0+/-1.5 mV [bumetanide], -66.0+/-1.5 mV to -59.8+/-2.8 mV [furosemide+bumetanide], n=11). However, only bumetanide was weakly, but significantly effective (-60.1+/-2.9 mV to -62.7+/-2.6 mV [bumetanide], -62.7+/-2.6 mV to -62.1+/-2.5 mV [furosemide+bumetanide], n=7) in P9-P12 homozygous (cir/cir) mice. CONCLUSION: The less prominent immunoreactivities and weak or absent responses to bumetanide or furosemide suggest impaired function or delayed development of both transporters in homozygous (cir/cir) mice.

Decreased Immunoreactivities and Functions of the Chloride Transporters, KCC2 and NKCC1, in the Lateral Superior Olive Neurons of Circling Mice

OBJECTIVES: We tested the possibility of differential expression and function of the potassium-chloride (KCC2) and sodium-potassium-2 chloride (NKCC1) co-transporters in the lateral superior olive (LSO) of heterozygous (+/cir) or homozygous (cir/cir) mice. METHODS: Mice pups aged from postnatal (P) day 9 to 16 were used. Tails from mice were cut for DNA typing. For Immunohistochemical analysis, rabbit polyclonal anti-KCC2 or rabbit polyclonal anti-NKCC1 was used and the density of immunolabelings was evaluated using the NIH image program. For functional analysis, whole cell voltage clamp technique was used in brain stem slices and the changes of reversal potentials were evaluated at various membrane potentials. RESULTS: Immunohistochemical analysis revealed both KCC2 and NKCC1 immunoreactivities were more prominent in heterozygous (+/cir) than homozygous (cir/cir) mice on P day 16. In P9-P12 heterozygous (+/cir) mice, the reversal potential (Egly) of glycine-induced currents was shifted to a more negative potential by 50 microM bumetanide, a known NKCC1 blocker, and the negatively shifted Egly was restored by additional application of 1 mM furosemide, a KCC2 blocker (-58.9+/-2.6 mV to -66.0+/-1.5 mV [bumetanide], -66.0+/-1.5 mV to -59.8+/-2.8 mV [furosemide+bumetanide], n=11). However, only bumetanide was weakly, but significantly effective (-60.1+/-2.9 mV to -62.7+/-2.6 mV [bumetanide], -62.7+/-2.6 mV to -62.1+/-2.5 mV [furosemide+bumetanide], n=7) in P9-P12 homozygous (cir/cir) mice. CONCLUSION: The less prominent immunoreactivities and weak or absent responses to bumetanide or furosemide suggest impaired function or delayed development of both transporters in homozygous (cir/cir) mice.

Bcl-2 Expression in the Developing Hair Follicle of Korean Fetal Scalp / 대한해부학회지

This study was intended to understand the role of the apoptosis-suppressing gene, bcl-2, in the hair follicle development. Immunohistochemistry for bcl-2 was performed using a high-throughput tissue-array technique, on Korean fetal scalp tissues at the 14 weeks, 16 weeks, 19 weeks & 24 weeks of the development. The results showed that the basal cells of epidermis were stained from 14 weeks to 24 weeks and the immunoreactive melanocytes were observed in the basal layer and suprabasal layer of epidermis as well as in the hair matrix cells and the external root sheath. At 19 weeks, the follicles at all stages of morphogenesis were observed. In the early stages, the epithelial cells of hair germ and hair peg, the mesenchymal cells surrounding them were stained. In the more advanced stage, the bcl-2 expression of follicular epithelial cells diminished to allow keratinization, hair canal formation and holocrine secretion to take place. In the bulbous hair peg stage, the hair papilla cells, the hair matrix cells, the basal cells of the primitive sebaceous gland, the primitive arrector pilli and the basal cells of the external root sheath were stained. We confirmed in the developing hair follicle that in the early stage or in the place where the cells continued to proliferate, the immature cells expressed bcl-2 to suppress cell death to overcome the susceptibility to cell death and when the differentiation was being achieved, the reduction of bcl-2 expression increased cell death to perform the tissue morphogenesis or the organ functions

The Effect of 835 MHz Radiofrequency Radiation Exposure on the Immunohistochemical Distribution of Calbindin D28k and Calretinin in the Mouse Cerebellar Cortex / 체질인류학회지

Widespread use of mobile phones and subsequent electromagnetic field (EMF) exposure have raised crucial question of their possible biological effects on the nervous system. The study on the effect of radiofrequency(RF) radiation on the nervous system, however, did not precede enough to determine the biological hazard to brain. Until now, several studies have reported decreases in neuron number and neuronal damage in the cortex, hippocampus, and basal ganglia in the brains of animals exposed to RF radiation. However, there were few reports about the cerebellum, the main voluntary motor control center. In this regard, by using immunohistochemisty, current study intended to investigate the changes in the calbindin D28k (CB) and calretinin (CR)-immunoreactivity (IR) in the mouse cerebellar cortex after EMF exposure at 835 MHz for different exposure times and absorption rates, 1 h/day for 5 days at 1.6 W/kg, 1 h/day for 5 days at 4.0 W/kg, 5 h/day for 1 day at 1.6 W/kg, 5 h/day for 1 day at 4.0 W/kg, daily exposure for one month at 1.6 W/kg. Among groups, most prominent CB IR was observed in the Purkinje cell layer followed by molecular and granular layer. The highest CB IR was noted in 5 h/day for 1 day at 1.6 W/kg in the entire three layers while the lowest was noted in one month at 1.6 W/kg. Similarly CR IR was maximum in one month at 1.6 W/kg whilst the lowest was observed in 1 h/day for 5 days at 4.0 W/kg. EMF exposure for 5 days at 1.6 W/kg reduced CB-IR. The CR-IR was mainly localized in small cells in the granular layer, with maximum IR observed after one month exposure. Therefore, the present study suggest the possibility of alterations of calcium ion concentration, which play a role in maintaining metabolic homeostasis, in the cerebellum after long-term exposure to 835 MHz of RF radiation, which might lead to thedisruption of normal trait.