• The Korean Journal of Physiology and Pharmacology
• /
• 제17권3호
• /
• pp.229-235
• /
• 2013

Among several animal models of retinitis pigmentosa (RP), the more recently developed rd10 mouse with later onset and slower rate of retinal degeneration than rd1 mouse is a more suitable model for testing therapeutic modalities. We therefore investigated the time course of retinal degeneration in rd10 mice before adopting this model in our interventional studies. Electroretinogram (ERG) recordings were carried out in postnatal weeks (PW) 3~5 rd10 (n=23) and wild-type (wt) mice (n=26). We compared the amplitude and implicit time of the b-wave of ERG records from wt and rd10 mice. Our results showed that b-wave amplitudes in rd10 mice were significantly lower and the implicit time of b-waves in rd10 mice were also significantly slower than that in wt mice ($20{\sim}160{\mu}V$ vs. $350{\sim}480{\mu}V$; 55~75 ms vs. 100~150 ms: p<0.001) through PW3 to PW5. The most drastic changes in ERG amplitudes and latencies were observed during PW3 to PW4. In multichannel recording of rd10 retina in PW2 to PW4.5, we found no significant difference in mean spike frequency, but the frequency of power spectral peak of local field potential at PW3 and PW3.5 is significantly different among other age groups (p<0.05). Histologic examination of rd10 retinae showed significant decrease in thickness of the outer nuclear layer at PW3. TUNEL positive cells were most frequently observed at PW3. From these data, we confirm that in the rd10 mouse, the most precipitous retinal degeneration occurs between PW3~PW4 and that photoreceptor degeneration is complete by PW5.

• Journal of Photoscience
• /
• 제3권3호
• /
• pp.127-132
• /
• 1996

Calcium has a variety of functions in neuron and muscle cells and blood clotting, especially in the visual system where dark adapted rods cotransport with Na$^+$ into the cell. An influx of Ca$^{2+}$ flows out of the cell through the Na$^+$ - Ca$^{2+}$ exchanger. By using a modified Ussing chamber in order to bring in vivo environment close, we have concluded that Ca$^{2+}$ blocks the activity of guanylate cyclase; in consequence, having an effect on the amplitude of electroretinogram (ERG). We suggest that Ca$^{2+}$ moves between the photoreceptor and the vitreous humor by way of certain Ca$^{2+}$ transport mechanisms. Also, the effect of Zn$^{2+}$ in Ca$^{2+}$ - free ringer solution caused an elevation of amplitude in ERG and a reduction of threshold.

• 한국임상수의학회:학술대회논문집
• /
• 한국임상수의학회 2009년도 춘계학술대회
• /
• pp.294-294
• /
• 2009

• 한국안광학회지
• /
• 제12권1호
• /
• pp.23-33
• /
• 2007

안구 조직에는 많은 양의 아연과 타우린이 존재하며 특히 망막에서 맥락막에 이르는 부위에서의 분포가 두드러지고, 이는 아연과 타우린이 이들 조직에서 중요한 역할을 담당하리라는 것을 시사한다. 또한 시각 감수성에 영향을 미치는 또 다른 인자로서, 온도에 대한 연구들이 보고되고 있다. 그러나 지금까지의 많은 연구에도 불구하고 시각 순응계에서의 이들의 기능이나 상호작용은 명확히 알려져 있지 않다. 본 연구에서는 변온동물의 일종인 황소개구리(bullfrog, Rana catesbeiana)의 안구를 이용하여 적정 농도의 아연과 타우린의 처리와 저온효과에 따른 망막전위도(ERG)와 흡수 스펙트럼의 변화를 관찰함으로써, 이들 인자들이 시각 감수성과 시각 순응에 미치는 효과를 알아보고자 하였다. 아연과 타우린의 효과를 알아보기 위한 이들의 적정 농도는 각각 10-4 M과 10-5 M로 결정하였고, 저온효과를 알아보기 위한 온도 변화 과정은'$25^{\circ}C {\rightarrow}0^{\circ}C{\rightarrow}25^{\circ}C$'를 거치게 하였다. 적정 농도의 아연과 타우린의 처리와 저온효과에 의해 망막전위도 실험 결과 역치(threshold)와 망막전위도 b-파의 크기가 증가하였고, 흡수 스펙트럼 분석 결과 400~750 nm 범위에서의 흡광도 증가를 볼 수 있었다. 또한 아연과 타우린, 그리고 아연과 저온효과 간에는 상승효과가 있음을 확인 할 수 있었다.

• 대한임상검사과학회지
• /
• 제53권3호
• /
• pp.266-276
• /
• 2021

안저 출혈은 망막 조직과 혈관의 이상을 의미한다. 따라서 안과 의사는 안저의 출혈성 변화가 발생하면 이에 따른 치료 계획을 수립하기 위해 치료 전과 치료 중간, 치료 이후 등 병변의 진행상황을 파악하기 위해 여러 가지 안과 검사의 출혈 성 정도의 평가를 위해 오더를 지시한다. 현재 가장 유용하고 보편적인 안저검사에는 빛간섭단층촬영(OCT), 안저촬영(FP), 형광안저혈관조영술(FAG) 등이 있다. 중증 안저 출혈에 대한 치료 계획을 수립하기 위한 기존의 형광안저혈관조영술 검사에는 한계가 있다. 저자들은 광각형광혈관조영술을 이용하여 동공주위촬영과 5-quadrant 방법을 수행할 것을 제안한다. 이 방법을 사용하면 신속히 검사 부위를 결정하고 최대한 출혈의 반경을 피해 안과 의사에게 손상된 조직과 이상 혈관의 범위를 제공할 수 있다. 그런데도 불구하고 안과 의사가 안저 출혈이 매우 심각하여 광각형광혈관조영술이 무의미하다고 판단하는 경우가 있다. 이런 경우 대체검사로 안과초음파 및 망막전위도의 오더가 발생한다. 따라서 우리는 안 초음파 및 망막전위도 검사 필요성에 대해 당위성을 인정해야 하고, 정확하게 수행해야 한다.

• 한국임상수의학회지
• /
• 제37권3호
• /
• pp.130-134
• /
• 2020

This study aimed to confirm the effects that the mobile phone has on Electroretinogram (ERG). The ERG responses of three groups of healthy dogs, five in each group, were studied. ERG test was performed consecutively before and after the mobile phone was carried out. For group A, music was played with the sound on; for group B, music was played but the sound off; and for group C, the phone was set on the airplane mode. In the presence of a mobile phone, the amplitudes of a- and b-wave were increased in all groups. The a- and b-wave amplitudes at the flash intensity of 3,000 mcd·s/㎡ were significantly increased in all groups (p < 0.05). Based on the results, it is recommended to conduct ERG test in the absence of a mobile phone for the accurate evaluation of the retinal function.

• 대한임상검사과학회지
• /
• 제43권2호
• /
• pp.33-42
• /
• 2011

Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

• Journal of Photoscience
• /
• 제6권2호
• /
• pp.77-83
• /
• 1999

Calcium has a variety of functions in neuron and muscle cells and blood clotting, especially in the visual system where dark adapted rods cotransport with Na$\^$+/ into the cell. An influx of Ca$\^$++/ flows out of the cell through the Na$\^$+/-Ca$\^$++/ exchanger. By using a modified Using chamber in order to bring in vivo environment close, we have known that Ca$\^$++/ blocks the activity of guanylate cyclase, in consequence, having an effect on the amplitude of electroretinogram (ERG). We have measured the Ca$\^$++/, K$\^$+/, and Na$\^$+/ concentration in dark and light adapted bullfrog＇s (Rana catesbeiana) vitreous humor. The calcium concentration of the light adapted bullfrog＇s vitreous humor was higher than that of the dark adapted bullfrog＇s vitreous humor This means that ion activity between the photoreceptor and vitreous humor side is light dependent and we have found that a Ca$\^$++/ channel and Ca$\^$++/K$\^$+/ exchanger exist in the vitreous humor side. Taken together permeability of Ca$\^$++/, K$\^$+/ and K$\^$+/ ion internal limiting membrane faced in the vitreous humor side has light-dependent activity during the illumination.

• 한국임상보건과학회지
• /
• 제4권4호
• /
• pp.756-761
• /
• 2016

Purpose. Noise occurs at measuring Electoretinogram(ERG) signals as the other bio-signal measurement. It is compared the denoising performance according to the mother function of wavelet transforms. Methods. The ERG signal that generated power supply noise and white noise was used as a sampling signal. The noise of ERG signal was filtered by using haar, db7, bior mother function. The filtering performance of each mother functions was compared using Fourier transform spectrum and SNR(signal to noise ratio). Results. In the haar functioin, the result of the Fourier transform spectrum was that the power supply noise is removed and the white noise performance is not good. The SNR was 27.0404. In the db7 function, the results of Fourier transform spectrum was that the power supply noise is removed and the white noise performance is good. The SNR was 35.1729. In the db7 function, the results of Fourier transform spectrum was that the power supply noise is removed and the white noise performance is the bset. The SNR was 35.4445. Conclusions. The db7, bior function was good results in power supply noise and white noise filtered. The bior function is suitable for filtering noise of the ERG signal.

• 수산해양기술연구
• /
• 제51권1호
• /
• pp.102-110
• /
• 2015

The characteristics of aquatic light fields are generally reflected in the visual systems of fishes inhabiting them. Therefore, research on light sensitivity of fish is useful to explain the correlation between the visual function and habitat, behavior and distribution of fish. Rockfish is an important species in coastal ecology and also one of the main species for culturing in Korea. To make a contribution on the maintenance of the fish resources and understanding the ecology of the rockfish, the visual spectral sensitivities of the dark-adapted rockfishes were measured in the range of visible light (405~660 nm) using a light source of light-emitting diodes (LEDs). In order to assess electrophysiological response of the fish, the ERGs (electroretinograms) of the dark-adapted rockfishes were recorded on a data logger (12 bits) and a laptop computer. Juvenile (n=5; weight: $20.3{\pm}5.2g$; total length: $10.3{\pm}0.7cm$) and adult (n=5; weight: $87.8{\pm}21.8g$; total length: $18.1{\pm}1.3cm$) rockfishes were used in experiment. The visual threshold of juvenile and adult rockfish were 11.66 (log quanta/$cm^2/s$) and 11.81 (log quanta/$cm^2/s$) in 574 nm, respectively. The peak wavelength of the spectral sensitivity in the dark-adapted juvenile and adult rockfish was commonly 551 nm (series of green color). Collectively, these results demonstrate that the rockfish has suitable visual capabilities for inhabiting coastal water in Korea.