This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Miranda-Anaya, M. Articles by Menaker, M. Search for Related Content PubMed PubMed Citation Articles by Miranda-Anaya, M. Articles by Menaker, M. Social Bookmarking                         What's this?

Circadian Rhythm of ERG in Iguana iguana: Role of the Pineal

Paul A. Bartell

Shin Yamazaki

Michael Menaker

Department of Biology and National Science Foundation, Center for Biological Timing, University of Virginia, Charlottesville, VA 22903, USA

In green iguanas, the pineal controls the circadian rhythm of body temperature but not the rhythm of locomotor activity. As part of a program to investigate the characteristics of this multioscillator circadian system, the authors studied the circadian rhythms of the electroretinographic response (ERG) and asked whether the pineal gland is necessary for the expression of this rhythm. ERGs from a total of 24 anesthetized juvenile iguanas were recorded under four different conditions: (a) complete darkness (DD), (b) dim light-dark cycles (dLD), (c) constant dim light (dLL), and (d) pinealectomized in DD. Results demonstrate that the b-wave component of the ERG shows a very clear circadian rhythm in DD and that this rhythm persists in dLL and entrains to dLD cycles. The ERG response is maximally sensitive during the subjective day. Pinealectomy does not abolish the circadian rhythm in ERG, demonstrating that the oscillator responsible for the ERG rhythm is located elsewhere.

Key Words: circadian rhythms • electroretinogram • Iguana iguana • pineal gland

Journal of Biological Rhythms, Vol. 15, No. 2, 163-171 (2000)
DOI: 10.1177/074873040001500210


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				P. A. Bartell, M. Miranda-Anaya, and M. Menaker Period and Phase Control in a Multioscillatory Circadian System (Iguana Iguana) J Biol Rhythms, February 1, 2004; 19(1): 47 - 57. [Abstract] [PDF]

				C. Bertolucci, G. Wagner, A. Foa, E. Gwinner, and R. Brandstatter Photoperiod Affects Amplitude but Not Duration of In Vitro Melatonin Production in the Ruin Lizard (Podarcis sicula) J Biol Rhythms, February 1, 2003; 18(1): 63 - 70. [Abstract] [PDF]

				M. Miranda-Anaya, P. A. Bartell, and M. Menaker Circadian Rhythm of Iguana Electroretinogram: The Role of Dopamine and Melatonin J Biol Rhythms, December 1, 2002; 17(6): 526 - 538. [Abstract] [PDF]

				M. Rufiange, M. Dumont, and P. Lachapelle Correlating Retinal Function with Melatonin Secretion in Subjects with an Early or Late Circadian Phase Invest. Ophthalmol. Vis. Sci., July 1, 2002; 43(7): 2491 - 2499. [Abstract] [Full Text] [PDF]

				J. F. Duffy and D.-J. Dijk Getting Through to Circadian Oscillators: Why Use Constant Routines? J Biol Rhythms, February 1, 2002; 17(1): 4 - 13. [Abstract] [PDF]

				W. Q. Wu, J. M. McGoogan, and V. M. Cassone Circadian Regulation of Visually Evoked Potentials in the Domestic Pigeon, Columba livia J Biol Rhythms, August 1, 2000; 15(4): 317 - 328. [Abstract] [PDF]