China
Africa
Explore chapters and articles related to this topic
Serotonin Modulation of Gastrointestinal Motility
Published in T.S. Gaginella, J.J. Galligan, SEROTONIN and GASTROINTESTINAL FUNCTION, 2020
Marcello Tonini, Fabrizio De Ponti
In the guinea pig, nerve-mediated 5-HT-induced nonadrenergic, noncholinergic (NANC) relaxations have been described in the longitudinal layer of proximal52–57 and distal colon,58 and in the circular muscle of the latter region.52 These relaxations are usually followed by contractions of mixed direct/indirect origin which, at least in the longitudinal layer, are mediated by 5-HT2, 5-HT3, and 5-HT4 receptors as reported below (but see Woollard, et al.29). Evidence against and in favor of 5-HT1 receptor participation in neurogenic colonic relaxations have been provided. Methysergide was found to be either ineffective52,53,58 or effective,55 as was metergoline.55,56 Like methysergide, methiothepin was found to be either ineffective57 or effective.54,56 The main inhibitory transmitter that mediates 5-HT-induced colonic relaxations is NO, although a minor participation of other transmitters such as ATP and VIP cannot be excluded.56
Anti-nociceptive effects of low dose ketamine in mice may be mediated by the serotonergic systems
Published in Psychiatry and Clinical Psychopharmacology, 2019
Meral Erdinc, Emre Uyar, Ilker Kelle, Hasan Akkoc
Drugs obtained from Sigma (St. Louis, MO, USA) were dissolved in saline and administered intraperitoneally (i.p.) in a volume of 0.1 ml/10 g body weight. Mice were separated into 14 groups (n = 8) and were treated with fluoxetine (20 mg/kg, 7 days) and a serotonin depleting agent; p-chlorophenylalanine (pCPA, 150 mg/kg, 4 days) or %0.9 saline. Drugs were administered once daily until the experiment day. A serotonin antagonist; methiothepin (0.1 mg/kg), an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor antagonist; GYKI-52466 (20 mg/kg), an analgesic; metamizole (500 mg/kg); and ketamine (20 mg/kg) were administered 60 mins before the test procedure. Doses of the drugs were selected according to previous studies. An HP test was performed for a single time for these groups. Three groups (vehicle, metamizole, and ketamine) were separated in order to test the sustained analgesic effect of ketamine. The HP test was performed for 6 consecutive times with a 1-hour break between each test [12].