Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

A morphological study of the circadian cycle of the pineal gland of the rat

  • 22 Accesses

  • 44 Citations

Summary

To seek a morphological expression of circadian rhythm, we investigated cytologically pineal glands taken from rats every 2 to 4 h under a lighting regime of 12 h of illumination (6:00 to 18:00) and 12 h of darkness. The changes in the number of synaptic ribbons and ribbon fields was observed by electron microscopy. The number of these intracellular elements was greatest at 2:00 and the lowest at 14:00, the difference being statistically significant. There were no significant local differences in numbers with respect to the part of the pineal gland examined. The data are similar to those of Vollrath from the pineal gland of a guinea pig, and seem to confirm a circadian function in the pineal gland in mammals.

This is a preview of subscription content, log in to check access.

References

  1. Alexander, B., Down, A.J., Wolfson, A.: Pineal hydroxyindole-O-methyltransferase (HIOMT) activity in female quail (Coturnix coturnix japonica). Neuroendocrinology 6, 236–246 (1970)

  2. Axelrod, J., Wurtman, R.J., Snyder, S.H.: Control of hydroxyindole-O-methyl transferase activity in rat pineal gland by environmental lighting. J. biol. Chem. 240, 949–954 (1965)

  3. Gaston, S., Menaker, M.: Pineal function: The biological clock in the sparrow: Science 160, 1125–1127 (1968)

  4. Kurumado, K., Mori, W.: A phylogenetic study on the pineal gland. Igaku-no-ayumi 94, 227–239 (1975) (in Japanese)

  5. Kurumado, K., Mori, W.: Synaptic ribbon in the human pinealocyte. Acta path. jap. 26, 381–384 (1976)

  6. Kurumado, K., Mori, W.: Sensory nerve elements in the human pineal gland. Acta path. jap. (1977) (in press)

  7. Quay, W.B.: Circadian rhythm in rat pineal serotonin and its modifications by estrous cycle and photoperiod. Gen. comp. Endocr. 3, 473–479 (1963)

  8. Quay, W.B.: 24-Hour rhythms in pineal 5-hydroxytryptamine and hydroxyindole-O-methyl transferase activity in the Macaque. Proc. Soc. exp. Biol. (N.Y.) 121, 946–949 (1966)

  9. Rønnekleiv, O.K., Krulich, L., McCann, S.M.: An early morning surge of prolactin in the male rat and its abolition by pinealectomy. Endocrinology 92, 1339–1342 (1973)

  10. Vollrath, L.: Synaptic ribbons of a mammalian pineal gland circadian changes. Z. Zellforsch. 145, 171–183 (1973)

  11. Vollrath, L., Huss, H.: The synaptic ribbons of the guinea-pig pineal gland under normal and experimental conditions. Z. Zellforsch. 139, 417–429 (1973)

  12. Wurtman, R.J., Axelrod, J., Phillips, L.S.: Melatonin synthesis in the pineal gland control by light. Science 142, 1071–1073 (1963)

Download references

Author information

Correspondence to Prof. Wataru Mori.

Additional information

Supported by grants-in-aid from the Ministry of Education, Science and Culture, and the Ministry of Health and Welfare

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Kurumado, K., Mori, W. A morphological study of the circadian cycle of the pineal gland of the rat. Cell Tissue Res. 182, 565–568 (1977). https://doi.org/10.1007/BF00219839

Download citation

Key words

  • Pineal gland (Rat)
  • Circadian rhythm
  • Synaptic ribbon