TY - JOUR
T1 - Effects of 5-hydroxytryptamine on defecation in open-field behavior in rats
AU - Kameyama, Tsutomu
AU - Suzuki, Masahiko
AU - Nabeshima, Toshitaka
PY - 1980/6
Y1 - 1980/6
N2 - An attempt was made to elucidate the role of the serotonergic nervous system in defecation resulting from environmental stimulation in rats. The open-field (OF) test and shuttle box method were used to study the defecation. 5-Hydroxytryptophan (5-HTP) significantly decreased the number of fecal boluses excreted in both emotional situations, namely, in both OF and shuttle box. The fecal excretion was significantly reduced compared with the controls after intraventricular injection of 5-hydroxytryptamine (5-HT). Animals pretreated with p-chlorophenylalanine (pCPA) and 5,6-dihydroxytryptamine (5,6-DHT) tended to show a slight increase in the OF defecation. 5-HTP was equally effective in diminishing the OF performance of pCPA-treated rats. The inhibitory effects of 5-HTP on the defecation were also observed after depletion of biogenic amines by reserpine treatment. Home cage defecation was increased after 5-HTP administration, decreased under pretreatment with pCPA and not influenced by intraventricular injection of 5-HT. These results suggested that the defecation after environmental stimuli was due to a change in 5-HT levels in the brain.
AB - An attempt was made to elucidate the role of the serotonergic nervous system in defecation resulting from environmental stimulation in rats. The open-field (OF) test and shuttle box method were used to study the defecation. 5-Hydroxytryptophan (5-HTP) significantly decreased the number of fecal boluses excreted in both emotional situations, namely, in both OF and shuttle box. The fecal excretion was significantly reduced compared with the controls after intraventricular injection of 5-hydroxytryptamine (5-HT). Animals pretreated with p-chlorophenylalanine (pCPA) and 5,6-dihydroxytryptamine (5,6-DHT) tended to show a slight increase in the OF defecation. 5-HTP was equally effective in diminishing the OF performance of pCPA-treated rats. The inhibitory effects of 5-HTP on the defecation were also observed after depletion of biogenic amines by reserpine treatment. Home cage defecation was increased after 5-HTP administration, decreased under pretreatment with pCPA and not influenced by intraventricular injection of 5-HT. These results suggested that the defecation after environmental stimuli was due to a change in 5-HT levels in the brain.
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U2 - 10.1016/0091-3057(80)90448-7
DO - 10.1016/0091-3057(80)90448-7
M3 - Article
C2 - 6447297
AN - SCOPUS:0018927888
SN - 0091-3057
VL - 12
SP - 875
EP - 882
JO - Pharmacology, Biochemistry and Behavior
JF - Pharmacology, Biochemistry and Behavior
IS - 6
ER -