Reference

Biphasic effects of m-chlorophenyl-piperazine on 3,4-dihydroxyphenylacetic acid concentration in rat brain

Biphasic effects of m-chlorophenyl-piperazine on 3,4-dihydroxyphenylacetic acid concentration in rat brain. Fuller, Ray W.; Snoddy, Harold D. (Lilly Res. Lab., Eli Lilly and Co., Indianapolis, Indiana, USA). Res. Commun. Chem. Pathol. Pharmacol., 17(3), 551-4 (English) 1977. CODEN: RCOCB8. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacodynamics) M-chlorophenylpiperazine-2HCl (I) [51639-49-7] injected i.p. into rats caused a rapid increase and a subsequent decrease in whole brain concn. of 3,4-dihydroxyphenylacetic acid (DOPAC) [102-32-9], a metabolite of dopamine [51-61-6]. The increase in DOPAC at 30 min and the decrease at 3 h were dose-related and occurred after doses as low as 5 mg I/kg.

Changes in sensitivity of 5-HT receptor mediated functional responses in the rat esophagus, fundus, and jejunum following chronic infusion with 5-hydroxytryptamine

Changes in sensitivity of 5-HT receptor mediated functional responses in the rat esophagus, fundus, and jejunum following chronic infusion with 5-hydroxytryptamine. McLean, Peter G.; Coupar, Ian M.; Molenaar, Peter (Victorian College Pharmacy, Monash University, Parkville 3052, Australia). Naunyn-Schmiedeberg's Archives of Pharmacology, 354(4), 513-519 (English) 1996 Springer. CODEN: NSAPCC. ISSN: 0028-1298. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Section cross-reference(s): 2 The effects of chronic infusion with 5-hydroxytryptamine (5-HT, 75 mg/kg per h) for 5 or 10 days in vivo on the responses of rat esophagus, fundus, and jejunum to 5-HT and partial 5-HT receptor agonists in vitro were investigated. In the rat esophagus, chronic treatment produced rightward shifts of the 5-HT4 receptor-mediated concn.-effect curves to 5-HT (dose-ratio = 3.8, day 5 and 2.8, day 10) and SC 53116 ( dose-ratio = 7.1, day 5 and 8.9, day 10) as compared to control tissues. The max. effect of 5-HT and SC 53116 in rat esophagus was reduced following the 10 day treatment. The 5-HT2B receptor-mediated contractile effect of 5-HT on rat fundus from treated animals responded with a significantly reduced potency (dose-ratio = 4.1, 5-day; 4.2, 10-day) compared to control tissues. The max. response to 5-HT was reduced in tissues from animals treated for 10 days. The concn.-effect curve to the partial agonist 1-(3-chlorophenyl)-piperazine dihydrochloride (mCPP) was shifted to the right in fundic tissue from treated animals (dose-ratio = 2.5, 5-day; 2.8, 10-day) compared to control tissues. The max. response to mCPP was also reduced in tissues from 5-HT treated animals. In jejunal tissues from treated animals, 5-HT produced its contractile effect in vitro with a 3.7 and 2.8 fold (5-day) and a 1.3 and 1.4fold (10-day) rightward shift of the first and second phase resp. of the control concn.-effect curve to 5-HT. The max.In this experiment, several chemicals are used like 50-67-9 and 51639-49-7 response produced by 5-HT in the first phase in jejunal tissues from animals treated for 10 days was significantly reduced by 49.1 %. These findings represent the first report that chronic infusion of 5-HT produces a residual desensitization of the 5-HT4, 5-HT2B, and putative 5-ht7/5-HT3 receptor-mediated responses in rat esophagus, fundus, and jejunum resp. when measured in vitro. .