Neuropeptide y and behaviorally induced phase shifts

doi:10.1016/0306-4522(94)90331-X

Neuroscience

Volume 62, Issue 1, September 1994, Pages 273-279

https://doi.org/10.1016/0306-4522(94)90331-X Get rights and content

Abstract

Neuropeptide Y-containing fibers project from the intergeniculate leaflet of the lateral geniculate nucleus to the suprachiasmatic nucleus. Previous studies have indicated that this pathway may be involved in non-photic resetting of the circadian clock. Therefore, we investigated the possibility that neuropeptide Y mediates phase shifts induced by a particular non-photic stimulus, a pulse of running in a novel wheel. Confining hamsters to a small nest box failed to block phase shifts induced by neuropeptide Y given at Zeitgeber time 4; this indicates that increased locomotor activity is not necessary for the observed shifts. Antiserum raised against neuropeptide Y or normal serum was administered at circadian time 5 through a cannula aimed at the suprachiasmatic nucleus. The hamsters were then removed from their cages and placed in a novel wheel for 3 h. Hamsters that received normal serum and ran > 5000 revolutions in the novel wheel advanced their rhythms (mean shift 2.55 h ± 0.22 S.E.M.) by amounts similar to those of unoperated hamsters. Administration of neuropeptide Y antiserum attenuated the shift normally associated with running in a novel wheel (mean shift 0.21 h ±0.14 S.E.M.).

These studies indicate that the neuropeptide Y input from the lateral geniculate nucleus to the biological clock is involved in the phase shifts seen in response to novelty-induced wheel running. It also provides another example of the ability of antisera to alter behavior. This may be a useful approach in manipulations of neurochemical activity when antagonists are not yet available or poorly denned.

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Citation Excerpt :
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^†: Present address: Division of Science, Northeast Missouri State University, Kirksville, MO 63501, U.S.A.

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Neuropeptide y and behaviorally induced phase shifts

Abstract

Neurosci. Lett.

Brain Res.

Brain Res.

Neurosci. Lett.

Brain Res. Bull.

Physiol. Behav.

Brain Res.

Physiol. Behav.

Brain Res.

Neuropeptide Y distribution in the rat brain

Science

Response curves in circadian periodicity

Bimodal effect of neuropeptide Y on feeding and its antagonism byreceptor blocking agents in rats

Acta physiol. hung.