Effect of skeleton photoperiod and food availability on the circadian pattern of feeding and drinking in rats.

University of Groningen EFFECT OF SKELETON PHOTOPERIOD AND FOOD AVAILABILITY ON THE CIRCADIAN PATTERN OF FEEDING AND DRINKING IN RATS

Forced dissociation of food- and light- entrainable circadian rhythms of rats in a skeleton photoperiod.

To investigate the control over drinking and feeding behavior by the light-entrainable circadian pacemaker, rats were maintained in a 12 h:12 h skeleton photoperiod for 36 days with both food and water restricted to the subjective day. During the restriction period most of the food and water intake was concentrated during the first 4 h of the subjective day. The subsequent release into ad lib c...

Photic and Pineal Modulation of Food Anticipatory Circadian Activity Rhythms in Rodents

Restricted daily feeding schedules entrain circadian oscillators that generate food anticipatory activity (FAA) rhythms in nocturnal rodents. The location of food-entrainable oscillators (FEOs) necessary for FAA remains uncertain. The most common procedure for inducing circadian FAA is to limit food access to a few hours in the middle of the light period, when activity levels are normally low. ...

Two possible determinants of the timing of daily episodes of behavior in rats.

The present experiment examined endogenous ultradian rhythms and regulatory metabolic processes as two potential determinants of daily out-of-nest episodes (ONEs) and feeding episodes (FEs) in rats living in a 24-h environment. Two types of photoperiod were used: a Standard 12:12 h L/D schedule and a Skeleton 12:12 h schedule. During each type of photoperiod rats were exposed to 4 feeding condi...

Organization of circadian rhythmicity and suprachiasmatic nuclei in malnourished rats.

The present study was aimed at characterizing the effects of low-protein malnutrition (6% casein) on the circadian rhythm of drinking behavior and on suprachiasmatic nuclei immunohistochemistry in Sprague-Dawley rats. Recordings were started at 30 days of age under a 12:12-h light-dark (LD) cycle. At age 150 days, recordings were continued under constant dim red light, and finally the latency t...