[Abstract Title]. - Society for Neuroscience

and found that there was a greater amplitude and shorter decay time of the AMPA/kainate
receptor-ionophore in cells recorded from control versus swim stressed rats. These results
indicate that repeated swim stress influences the pPVTh by altering basic firing properties,
afferent input and receptor mediated responses. Furthermore, the effect of orexin is not the same
on the firing pattern of repeated swim compared to control rats. Together, these results indicate
that repeated stress alters orexin actions in the pPVTh. These alterations may underlie the
differential neuroendocrine and behavioral response observed in repeatedly vs. acutely stressed
rats following manipulation of orexin receptors.
Disclosures: S. Bhatnagar , None; D. Piehl, None; V. Iyer, None; S. Beck, None.
Poster
282. Stress and the Brain: Cellular Actions of Stress
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 282.7/OO14
Topic: E.06.d. Cellular actions of stress
Title: Effects of low intensity exercise on neuronal activation of serotonergic neurons in the
dorsal raphe nucleus and anxiety-like behavior in rats
Authors: T. OTSUKA, N. KUBOTA, S. YANAGITA, *I. KITA;
Dept Human Hlth. Sci., Tokyo Metropolitan Univ., Hachioji, Tokyo, Japan
Abstract: Several studies have suggested that depression and anxiety respond to the same
treatments, including selective serotonin reuptake inhibitors and physical exercise, and that
serotonin (5-HT) neurons in the dorsal raphe nucleus (DRN) are implicated in
antidepressant/anxiolytic properties. It is, thus, possible that physical exercise produces its
antidepressant/anxiolytic properties by affecting neuronal activity of DRN 5-HT neurons.
Chronic exercise using running wheel or treadmill is known to increase the activity of 5-HT
neurons in the DRN and turnover of 5-HT in the cortex. On the other hand, it is reported that
chronic wheel running could attenuate stress-induced c-Fos induction in 5-HT neurons in the
DRN and increase mRNA level of 5-HT1A autoreceptor in the DRN, suggesting that activation
of 5-HT neurons during acute physical exercise might mitigate excessive 5-HT activity to stress
events. However, effects of acute physical exercise on neuronal activity of DRN 5-HT neurons,
or relationship between the exercise intensity and the neuronal activity of 5-HT are unknown. In
addition, since stressful life events are related to incidence and symptom of depression and
anxiety, corticotropin-releasing factor (CRF) neurons in the hypothalamic paraventricular
nucleus (PVN), which play an important role as one of the central activators of integrated stress
response, may be also involved in antidepressant/anxiolytic properties by physical exercise. The