THE c‐WAVE OF THE HUMAN D.C. REGISTERED ERG. III. EFFECTS OF ETHYL ALCOHOL ON THE c‐WAVE

Self Cite

The effects of ethanol on the human standing potential (SP) were studied with a recently developed method, which allows direct SP recordings by means of a suction contact lens, temperature stabilized calomel electrodes and d.c. amplification. It is well known that the human SP oscillates with a frequency of about 2/hour in response to a sudden change in illumination. In the present paper marked cyclic variations of the SP, resembling damped oscillations, were provoked by a small oral dose of ethyl alcohol. A first maximum was reached after about 10 min. The difference in amplitude between the peak and the trough of the first oscillation was of the order of 4 mV. The oscillatory frequency was about 2/hour. The length of a cycle varied between 25 and 34 min in different volunteers, being fairly constant in the same subject on different occasions. The SP response to ethanol was similar both under scotopic and photopic conditions. The results correlate well with earlier findings of 2/hour oscillations in c-wave amplitude in response to ethanol, as may be expected considering the partly common origin of the c-wave and the SP.

Section: Discussionsupporting

confidence: 73%

mentioning

confidence: 98%

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of Ethyl Alcohol on the Directly Recorded Standing Potential of the Human Eye

Skoog

Textorius

Nilsson

1975

Self Cite

“…These results are in accordance with previous reports which describe the a-wave to increase after intravenous or intravitreal injections of ethyl alcohol (Jacobson et al 1969;Morita 1970). However, Ikeda (1963) and Skoog (1974) found no effect on the a-wave of the human ERG and Bernhard et al (1973) found a decrease of the a-wave of the sheep ERG after ethanol administration.…”

Section: Discussionmentioning

confidence: 87%

Further Studies of the Chemical Sensitivity of the Oscillatory Potentials of the Electroretinogram (Erg)

Wachtmeister

1981

The action of some omega amino acids and the influence of ethanol on the oscillatory potentials (OPs) of the ERG were tested. Low doses of beta-alanine, an inhibitory amino acid, selectively suppressed the amplitude of the OPs without affecting the a- and b-waves. The earlier OPs (O1 O2) appeared somewhat more sensitive to the drug than the later ones (O3-O5). Higher doses extinguished all the OPs but also affected the maximum amplitude of the a- and b-wave. There was no noticeable change of the threshold sensitivity of the a- and b-waves. Valine in corresponding concentrations did not affect the OPs. Taurine did not change the OPs in most experiments but in some experiments a concurrent decrease of the OPs, a- and b-waves occurred. Thus, these findings support the view that only inhibitory feed-back circuits initiated by the amacrines give rise to the OPs. Ethanol had a differential and selective effect on the OPs. The later OPs (O3-O5) were sensitive to ethanol. In conclusion, these results support the notion that the individual oscillatory peaks are likely to have different origins and that the later OPs may perhaps be related to the off-components in response to brief stimulus light.

“…In the retina, several toxins, such as, dimethylaminopentane (Nakajima 1958 b), dinitrofluorobenzene (Nakajima 195 8a), melanonitrile (Nakajima 1958a), ouabain (Honda 1972), cephaloridine (Honda & Nagata 1975), diphenylhydantoin (Honda et al 1973), ethanol (Potts 1955;Honda 1977) have been shown to temporarily increase the ERG b-wave amplitude at an initial phase when applied in low concentrations. .In sheep (Knave et al 1974) and man (Skoog 1974), low doses of ethanol enhance the c-wave. As apparent toxins such as NaIO3 also enhance the electric activity of the pigment epithelium in low concentration, these findings should be kept in mind when discussing the effects of chemical dosage in toxicological studies.…”

Section: Discussionmentioning

confidence: 96%

Paradoxical enhancement of the ERG c‐wave by a small dose of sodium iodate

Nao‐i

Kim

Honda

1986

The early effects of sodium iodate (NaIO3) on the ERG c- and b-waves were studied in rabbits. When 30 mg NaIO3/kg body weight was administered intravenously, the c-wave amplitude decreased and was replaced by a potential of opposite polarity. However, the administration of 20 mg/kg of NaIO3 enhanced the c-wave remarkably. Twenty min after administration, the mean c-wave amplitude significantly increased (P less than 0.001) to 211 +/- 6.2% of the pre-administration amplitude, whereas that of the control was 108 +/- 13.0%. The b-wave amplitude showed no significant changes. When 10 mg/kg of NaIO3 was administered, the enhancement of the c-wave was not remarkable. These effects were similar in both pigmented and albino rabbits. A lower blood concentration of NaIO3 applied to the basal side of the retinal pigment epithelium (RPE) may initially affect only the basal membrane of the RPE resulting in the decrease in the basal membrane resistance (Rba). This would explain the transient increase in the c-wave amplitude with 20 mg NaIO3/kg.