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. 1968 Oct 1;52(4):584–599. doi: 10.1085/jgp.52.4.584

Thermal and Spectral Sensitivities of Discrete Slow Potentials in Limulus Eye

Alan R Adolph 1
PMCID: PMC2225835  PMID: 5682485

Abstract

The discrete, subthreshold, slow potential fluctuations (SPF's) which can be recorded intracellularly in Limulus ommatidia are sensitive to temperature and light wavelength. SPF frequency increases with increasing temperature (Q10 about 3.5) and light intensity. The effects are additive. SPF rise and decay time decrease with increasing temperature (Q10 between 2 and 3). There is a peak, near 520 nm, in the spectral sensitivity of SPF frequency. This peak may correspond to the wavelength of maximum absorption by rhodopsin in the ommatidia. Hydroxylamine produces a rapid, irreversible reduction of SPF frequency and amplitude perhaps owing to its action on the photopigment. The cornea and crystalline cones fluoresce (peak about 445 nm) when excited by near-ultraviolet energy (380 nm peak) and this fluorescence may influence SPF spectral sensitivity measurements. These findings suggest that the SPF's are the results of photolytic and thermolytic reactions occurring in the ommatidial visual pigments and that they have a role in the mechanisms which transduce light to electrical activity in the visual receptors.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ADOLPH A. R. SPONTANEOUS SLOW POTENTIAL FLUCTUATIONS IN THE LIMULUS PHOTORECEPTOR. J Gen Physiol. 1964 Nov;48:297–322. doi: 10.1085/jgp.48.2.297. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. BENOLKEN R. M. Reversal of photoreceptor polarity recorded during the graded receptor potential response to light in the eye of Limulus. Biophys J. 1961 Sep;1:551–564. doi: 10.1016/s0006-3495(61)86908-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Behrens M. E., Wulff V. J. Light-initiated responses of retinula and eccentric cells in the Limulus lateral eye. J Gen Physiol. 1965 Jul;48(6):1081–1093. doi: 10.1085/jgp.48.6.1081. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Chapman R. M., Lall A. B. Electroretinogram characteristics and the spectral mechanisms of the median ocellus and the lateral eye in Limulus polyphemus. J Gen Physiol. 1967 Oct;50(9):2267–2287. doi: 10.1085/jgp.50.9.2267. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. HARTLINE H. K., WAGNER H. G., MACNICHOL E. F., Jr The peripheral origin of nervous activity in the visual system. Cold Spring Harb Symp Quant Biol. 1952;17:125–141. doi: 10.1101/sqb.1952.017.01.013. [DOI] [PubMed] [Google Scholar]
  6. HUBBARD R. Bleaching of rhodopsin by light and by heat. Nature. 1958 Apr 19;181(4616):1126–1126. doi: 10.1038/1811126a0. [DOI] [PubMed] [Google Scholar]
  7. HUBBARD R., WALD G. Visual pigment of the horseshoe crab, Limulus polyphemus. Nature. 1960 Apr 16;186:212–215. doi: 10.1038/186212b0. [DOI] [PubMed] [Google Scholar]
  8. Hecht S. PHOTOCHEMISTRY OF VISUAL PURPLE : II. THE EFFECT OF TEMPERATURE ON THE BLEACHING OF VISUAL PURPLE BY LIGHT. J Gen Physiol. 1921 Jan 20;3(3):285–290. doi: 10.1085/jgp.3.3.285. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Hubbard R., Bownds D., Yoshizawa T. The chemistry of visual photoreception. Cold Spring Harb Symp Quant Biol. 1965;30:301–315. doi: 10.1101/sqb.1965.030.01.032. [DOI] [PubMed] [Google Scholar]
  10. Millecchia R., Bradbury J., Mauro A. Simple photoreceptors in Limulus polyphemus. Science. 1966 Dec 2;154(3753):1199–1201. doi: 10.1126/science.154.3753.1199. [DOI] [PubMed] [Google Scholar]
  11. SCHOLES J. H. DISCRETE SUBTHRESHOLD POTENTIALS FROM THE DIMLY LIT INSECT EYE. Nature. 1964 May 9;202:572–573. doi: 10.1038/202572a0. [DOI] [PubMed] [Google Scholar]
  12. SMITH T. G., BAUMANN F., FUORTES M. G. ELECTRICAL CONNECTIONS BETWEEN VISUAL CELLS IN THE OMMATIDIUM OF LIMULUS. Science. 1965 Mar 19;147(3664):1446–1448. doi: 10.1126/science.147.3664.1446. [DOI] [PubMed] [Google Scholar]
  13. WALD G., BROWN P. K., GIBBONS I. R. The problem of visual excitation. J Opt Soc Am. 1963 Jan;53:20–35. doi: 10.1364/josa.53.000020. [DOI] [PubMed] [Google Scholar]
  14. WALD G., KRAININ J. M. THE MEDIAN EYE OF LIMULUS: AN ULTRAVIOLET RECEPTOR. Proc Natl Acad Sci U S A. 1963 Dec;50:1011–1017. doi: 10.1073/pnas.50.6.1011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Wald G., Brown P. K. The Synthesis of Rhodopsin from Retinene(1). Proc Natl Acad Sci U S A. 1950 Feb;36(2):84–92. doi: 10.1073/pnas.36.2.84. [DOI] [PMC free article] [PubMed] [Google Scholar]

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