Periodic feeding has been shown to synchronize a number of physiological and behavioral rhythms. In the present study, three experiments were carried out to investigate the role of periodic food availability in the regulation of the physiology of the gastrointestinal (G.I.) tract. In experiment one, measurements of body weight and gastric capacity were obtained from rats exposed to 2, 5, 8, 12, and 17 weeks of restricted feeding (RF), with 4 h of food access per day. Subjects exposed to only two weeks of RF exhibited the greatest decline in body weight (17.8%), while increasing exposure to RF resulted in body weight gain. Gastric area and capacity measurements were lowest in the 2 week group and largest in the 12 and 17 week groups. These changes appear to be of an adaptive rather than of a pathological nature. In experiment two, subdiaphragmatic sections of the vagus nerve were shown not to disrupt the expression of activity rhythms previously entrained by periodic food availability. In the third experiment, simultaneous recordings of G.I. electromyograms and bar pressing for food were obtained during ad lib. feeding, food deprivation, RF, and phase shifts of food access. During ad lib. feeding large amplitude slow potentials associated with irregular contractions (IC) of duodenal origin were observed 2 to 4 h prior to the onset of the dark phase of the LD cycle. ICs were also observed during RF, 3 to 5 h preceding food access. The distribution of ICs showed a circadian variation during food deprivation and transients were observed in response to 6 or 8 h phase delays of food access. This suggests that ICs are modulated by a circadian mechanism. On the average, the increase in ICs occurred about 2 h earlier than barpressing in anticipation of food and there was no specific relation between individual ICs and bar pressing. / Source: Dissertation Abstracts International, Volume: 48-07, Section: B, page: 2135. / Thesis (Ph.D.)--The Florida State University, 1987.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76139 |
| Contributors | COMPERATORE, CARLOS ARTURO., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 181 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
Page generated in 0.0018 seconds