Summary
Djungarian hamsters (Phodopus sungorus sungorus) depend mainly on day length to cue seasonal adjustments. However, not all individuals respond to short day conditions. A previous study from this laboratory proposed that nonresponsiveness to short day conditions rests with a defect in the circadian organization of these hamsters.
In this study we found pronounced differences between responsive and nonresponsive hamsters in the expression of circadian rhythmicity under constant darkness and under constant illumination. While responsive hamsters showed a free-running activity pattern with a period of 23.86+0.04 h and responded to brief light pulses with the expected phase delays and phase advances, nonresponsive hamsters exhibited a period of 24.04+0.05 h and responded to light pulses with phase advances. Furthermore, 9 out of 15 responsive hamsters showed a clear split in the activity pattern within 8 weeks under constant light (80–100 lux), while only 1 of the 7 nonresponsive hamsters exhibited a split activity pattern. As a result of these differences in circadian function, nonresponsive Djungarian hamsters are incapable of proper photoperiod time measurement and photoperiod-induced seasonality.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- PRC :
-
phase response curve
- ct :
-
circadian time
- DD :
-
constant dark
- LL :
-
constant light
References
Boulos Z, Morin LP (1985) Entrainment of split circadian activity rhythm in hamsters. J Biol Rhythms 1:1–15
Daan S, Berde C (1978) Two coupled oscillators: Simulation of the circadian pacemaker in mammalian activity rhythms. J Theor Biol 70:297–313
Daan S, Pittendrigh CS (1976) A functional analysis of circadian pacemakers in nocturnal rodents. II. The variability of phase response curves. J Comp Physiol 106:253–266
Darrow JM, Goldman BD (1985) Circadian regulation of pineal melatonin and reproduction in the Djungarian hamster. J Biol Rhythms 1:39–54
Duncan MJ, Goldman BD, DiPinto N, Stetson MH (1985) Testicular function and pelage color have different critical photoperiods in the Djungarian hamster,Phodopus sungorus. Endocrinology 116:424–430
Elliott JA (1976) Circadian rhythm and photoperiodic time measurement in mammals. Fed Proc 35:2339–2346
Figala J, Hoffmann K, Goldau G (1973) Zur Jahresperiodik beim Dsungarischen Zwerghamster,Phodopus sungorus Pallas. Oecologia 12:89–118
Heldmaier G, Steinlechner S (1981a) Seasonal control of energy requirement for thermoregulation in the Djungarian hamster (Phodopus sungorus), living in natural photoperiod. J Comp Physiol 142:429–437
Heldmaier G, Steinlechner S (1981b) Seasonal pattern and energetic of short daily torpor in the Djungarian hamsterPhodopus sungorus. Oecologia 48:265–270
Heldmaier G, Steinlechner S, Rafael J (1982) Nonshivering thermogenesis and cold resistance during seasonal acclimatization in the Djungarian hamster. J Comp Physiol 149: 1–9
Hoffmann K (1973) The influence of photoperiod and melatonin on testis size, body mass, and pelage colour in the Djungarian hamster (Phodopus sungorus). J Comp Physiol 85:267–282
Hoffmann K (1982) The critical photoperiod in the Djungarian hamsterPhodopus sungorus. In: Aschoff J, Daan S, Gross G (eds) Vertebrate circadian systems. Springer, Berlin Heidelberg New York, pp 297–304
Illnerova H, Hoffmann K, Vanecek J (1984) Adjustment of pineal melatonin and N-acetyltransferase rhythms to changes from long to short photoperiod in the Djungarian hamsterPhodopus sungorus. Neuroendocrinology 38:226–231
Lynch GR, Lynch CB (1986) Seasonal photoperiodism in the Djungarian hamster. A genetic component influences photoresponsiveness. Behav Genet 16:625–626
Lynch GR, Puchalski W (1986) Effects of prolonged short day exposure on thermoregulation in the Djungarian hamster (Phodopus sungorus). In: Heller HC, Musacchia XJ, Wang LCH (eds) Living in the cold. Elsevier, New York, pp 317–322
Milette J, Turek FW (1986) Circadian and photoperiodic effects of brief light pulses in male Djungarian hamsters. Biol Reprod 35:327–335
Moore RY, Klein DC (1974) Visual pathways and the central neuronal control of a circadian rhythm in pineal serotonin N-acetyltransferase activity. Brain Res 71:17–33
Pavlidis T (1973) Biological oscillators: their mathematical analysis: phase shifts and phase response curves. Academic Press, New York, pp 49–70
Pittendrigh CS, Daan S (1976a) A functional analysis of circadian pacemakers in nocturnal rodents. IV. Entrainment: pacemaker as clock. J Comp Physiol 106:291–331
Pittendrigh CS, Daan S (1976b) A functional analysis of circadian pacemakers in nocturnal rodents. V. Pacemaker structure: a clock for all seasons. J Comp Physiol 106:333–355
Puchalski W, Lynch GR (1986) Evidence for differences in the circadian organization of hamsters exposed to short day photoperiod. J Comp Physiol A 159:7–11
Rafael J, Vsiansky P, Heldmaier G (1985) Seasonal adaptation of brown adipose tissue in the Djungarian hamster. J Comp Physiol B 155:521–528
Steinlechner S, Heldmaier G, Becker H (1983) The seasonal cycle of body weight in the Djungarian hamster: photoperiodic control and the influence of starvation and melatonin. Oecologia 60:401–405
Stetson ME, Watson-Whitmyre M (1976) Nucleus suprachiasmaticus: The biological clock in the hamster? Science 191:197–199
Turek FW, Earnest DJ, Swann J (1982) Splitting of the circadian rhythm of activity in hamsters. In: Aschoff J, Daan S, Gross G (eds) Vertebrate circadian systems. Springer, Berlin Heidelberg New York, pp 203–214
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Puchalski, W., Lynch, G.R. Characterization of circadian function in Djungarian hamsters insensitive to short day photoperiod. J. Comp. Physiol. 162, 309–316 (1988). https://doi.org/10.1007/BF00606119
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00606119