1
|
de Sousa LN, Sant'ana DSP, Siqueira dos Santos RG, dos Santos Ribeiro AEA, da Costa CF, de Oliveira AP, Almeida JRGDS, Jucá DM, da Silva MTB, dos Santos AA, Palheta Junior RC. Involvement of serotonergic pathways in gastric dysmotility induced by fat burning nutritional supplements in mice. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2021; 2:100018. [PMID: 34909653 PMCID: PMC8663933 DOI: 10.1016/j.crphar.2021.100018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/20/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022] Open
Abstract
Fat burners are a category of nutritional supplements that are claimed to increase the metabolism and promote greater energy expenditure, leading to weight loss. However, little is known about the side effects on gastrointestinal motility. In this study, we evaluated the effect of ingestion with a fat burner named Thermbuterol® (THERM) on the gastric motility and food behavior of mice. THERM compounds were identified using nuclear magnetic resonance (NMR). Mice received variable doses of THERM (10, 50, 100 or 300 mg/kg, p.o.) or NaCl 0.15 M (control). Gastric emptying (GE) was assessed using the phenol red technique. Another set of mice was pretreated with intraperitoneal administration of hexamethonium (HEXA, 10 mg/kg), prazosin (PRAZ, 0.25 mg/kg), propranolol (PROP, 2 mg/kg), parachlorophenylalanine (PCPA, 300 mg/kg) or ondansetron (ONDA, 50 μg/kg) 30 min before THERM treatment for evaluation of GE. We assessed the gastrointestinal responsiveness in vitro as well as THERM's effects on food behavior. Caffeine was the major compound of THERM, identified by NMR. THERM 100 and 300 mg/kg decreased GE compared to the respective controls. Pretreatment with PRAZ or PROP did not prevent gastric dysmotility induced by THERM 100 mg/kg. However, the pretreatment with HEXA, ONDA or PCPA prevented GE delay induced by THERM. In vitro, THERM relaxed contractions in strips of longitudinal gastric fundus and duodenum. THERM also increased food intake, which was prevented by PCPA and ONDA treatments. THERM decreased GE of a liquid and increased food intake in mice, a phenomenon mediated by the autonomic nicotinic receptors and serotoninergic receptor.
Collapse
Affiliation(s)
| | | | | | | | - Camila F. da Costa
- Federal University of São Francisco Valley, Petrolina, Pernambuco, Brazil
| | | | | | - Davi M. Jucá
- Belo Horizonte University Center, Cristiano Machado Campus. Belo Horizonte, Minas Gerais, Brazil
| | - Moisés Tolentino Bento da Silva
- Laboratory of Exercise and Gastrointestinal Tract – Department of Physical Education, Federal University of Piauí, Teresina, Piauí, Brazil
| | - Armênio A. dos Santos
- Department of Physiology and Pharmacology, School of Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | |
Collapse
|
2
|
Efficacy of palonosetron versus ramosetron on preventing opioid-based analgesia-related nausea and vomiting after lumbar spinal surgery: a prospective, randomized, and double-blind trial. Spine (Phila Pa 1976) 2014; 39:E543-9. [PMID: 24480956 DOI: 10.1097/brs.0000000000000236] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A prospective, randomized, and double-blind study. OBJECTIVE To compare the efficacy of ramosetron and palonosetron on preventing postoperative nausea and vomiting (PONV) associated with opioid-based intravenous patient-controlled analgesia (IV-PCAopioid) after lumbar spinal surgery. SUMMARY OF BACKGROUND DATA IV-PCAopioid, an effective method to control pain after lumbar spinal surgery, accompanies PONV. Ramosetron and palonosetron are novel 5-hydroxytryptamine 3 antagonists known to have longer action duration and higher receptor affinity than their congeners, whereas their relative efficacy has not been validated yet. METHODS One hundred ninety-six patients were randomly and evenly allocated to receive either 0.3 mg of ramosetron or 0.075 mg of palonosetron 10 minutes before the end of operation. Ramosetron or palonosetron were also added to the IV-PCAopioid, which was continuously infused for 48 hours postoperatively. The incidence and intensity of PONV were serially assessed for 72 hours postoperatively. Intensity of pain, volume of IV-PCAopioid consumption, use of rescue analgesics and antiemetics, and adverse events were also assessed. RESULTS The overall incidence of PONV was lower in the ramosetron group than the palonosetron group (50% vs. 67%, P = 0.014) without any intergroup difference in the incidence of vomiting. Nausea intensity scores were also lower until 6 (P = 0.041) and 24 hour (P = 0.026) postoperatively in the ramosetron group than the palonosetron group. Pain intensity scores were significantly lower in the ramosetron group than the palonosetron group for 72 hours postoperatively. CONCLUSION Ramosetron was superior to palonosetron in term of reducing the incidence and severity of nausea associated with IV-PCAopioid after lumbar spinal surgery. This favorable influence of ramosetron on PONV was translated to significant postoperative pain reduction compared with palonosetron. LEVEL OF EVIDENCE 1.
Collapse
|
3
|
Huang J, Wang XJ, Yu D, Jin YN, Zhen LZ, Xu N, Liu W, Deng YC, Wu SX, He J. The effect of palonosetron hydrochloride in the prevention of chemotherapy-induced moderate and severe nausea and vomiting. Exp Ther Med 2013; 5:1418-1426. [PMID: 23737892 PMCID: PMC3671900 DOI: 10.3892/etm.2013.996] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 01/14/2013] [Indexed: 11/22/2022] Open
Abstract
The current study aimed to evaluate the efficacy and safety of palonosetron hydrochloride injection for preventing chemotherapy-induced moderate and severe nausea and vomiting. A multi-centered, randomly stratified, double-blind, double-dummy, parallel-group and positive-controlled trial was performed. A total of 240 patients who underwent chemotherapy treatment which induced moderate or severe vomiting were divided into the experimental and control groups. Half an hour before chemotherapy, the experimental group received a 0.25-mg palonosetron hydrochloride injection, whereas the control group received a 3-mg granisetron injection. The acute vomiting complete remission rate (CRR) of the experimental group was not significantly different compared with that of the control group (P=0.35). The delayed vomiting CRR of the experimental group was significantly higher compared with that of the control group (P=0.002). No difference in full course vomiting CRR, vomiting control time, treatment failure time or acute nausea CRR was identified between the two groups. No significant differences in adverse events were observed between the experimental group and the control group. No significant differences in adverse reactions occurred between the experimental group and the control group (12.50%). Palonosetron hydrochloride injection had a better effect on delayed vomiting CRR than granisetron hydrochloride injection. The two injections exhibited similar effects on acute vomiting CRR, full course vomiting CRR, vomiting control time, treatment failure time (days), acute nausea CRR and adverse events.
Collapse
Affiliation(s)
- Jian Huang
- Zhejiang Cancer Hospital, Hangzhou 310022
| | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Duffy NH, Lester HA, Dougherty DA. Ondansetron and granisetron binding orientation in the 5-HT(3) receptor determined by unnatural amino acid mutagenesis. ACS Chem Biol 2012; 7:1738-45. [PMID: 22873819 DOI: 10.1021/cb300246j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The serotonin type 3 receptor (5-HT(3)R) is a ligand-gated ion channel found in the central and peripheral nervous systems. The 5-HT(3)R is a therapeutic target, and the clinically available drugs ondansetron and granisetron inhibit receptor activity. Their inhibitory action is through competitive binding to the native ligand binding site, although the binding orientation of the drugs at the receptor has been a matter of debate. Here we heterologously express mouse 5-HT(3)A receptors in Xenopus oocytes and use unnatural amino acid mutagenesis to establish a cation-π interaction for both ondansetron and granisetron to tryptophan 183 in the ligand binding pocket. This cation-π interaction establishes a binding orientation for both ondansetron and granisetron within the binding pocket.
Collapse
Affiliation(s)
- Noah H. Duffy
- Division
of Chemistry and Chemical Engineering and ‡Division of Biology, California Institute of Technology,
Pasadena, California 91125, United States
| | - Henry A. Lester
- Division
of Chemistry and Chemical Engineering and ‡Division of Biology, California Institute of Technology,
Pasadena, California 91125, United States
| | - Dennis A. Dougherty
- Division
of Chemistry and Chemical Engineering and ‡Division of Biology, California Institute of Technology,
Pasadena, California 91125, United States
| |
Collapse
|
5
|
Ayuhara H, Takayanagi R, Okuyama K, Yoshimoto K, Ozeki T, Yokoyama H, Yamada Y. Receptor occupancy theory-based analysis of interindividual differences in antiemetic effects of 5-HT3 receptor antagonists. Int J Clin Oncol 2009; 14:518-24. [PMID: 19967488 DOI: 10.1007/s10147-009-0912-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Accepted: 05/24/2009] [Indexed: 11/24/2022]
Abstract
BACKGROUND The aim of this study was to estimate interindividual differences in the antiemetic effects of 5-HT(3) receptor antagonists by evaluating the influence of pharmacokinetics on 5-HT(3) receptor occupancies, based on receptor occupancy theory. METHODS We analyzed interindividual differences of 5-HT(3) receptor occupancies and antiemetic effects after the oral and/or intravenous administration of standard doses of the following 5-HT(3) receptor antagonists: azasetron, granisetron, indisetron, ondansetron, ramosetron, and tropisetron. RESULTS The interindividual difference between maximum and minimum 5-HT(3) receptor occupancies after oral administration ranged from 0.6% to 64.0%, and that difference after intravenous administration ranged from 0.6% to 29.6%. Following oral administration, the interindividual difference between maximum and minimum complete vomiting inhibition rates ranged from 0.2% to 16.1%. After intravenous administration, that difference ranged from 0.8% to 52.5%. CONCLUSION Interindividual differences in the clinical effects of 5-HT(3) receptor antagonists could be evaluated based on receptor occupancy theory, and the differences varied among drugs. Drug selection considering these individual variations might be useful for the patients who experienced vomiting associated with chemotherapy.
Collapse
Affiliation(s)
- Hideaki Ayuhara
- Department of Clinical Evaluation of Drug Efficacy, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | | | | | | | | | | | | |
Collapse
|
6
|
Faerber L, Drechsler S, Ladenburger S, Gschaidmeier H, Fischer W. The neuronal 5-HT3 receptor network after 20 years of research — Evolving concepts in management of pain and inflammation. Eur J Pharmacol 2007; 560:1-8. [PMID: 17316606 DOI: 10.1016/j.ejphar.2007.01.028] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2006] [Accepted: 01/09/2007] [Indexed: 11/19/2022]
Abstract
The 5-HT3 receptor is a pentameric ligand-gated cation channel which is found in the central and peripheral nervous system and on extraneuronal locations like lymphocytes, monocytes and fetal tissue. Five monomer subtypes, the 5-HT(3A-E) subunits, have been identified which show differences in the amino-terminal and the transmembrane region. The functional relevance of different receptor compositions is not yet clarified. 5-HT3 receptors are located predominantly in CNS regions that are involved in the integration of the vomiting reflex, pain processing, the reward system and anxiety control. The preferential localization on nerve endings is consistent with a physiological role of 5-HT3 receptors in the control of neurotransmitter release such as dopamine, cholecystokinin, glutamate, acetylcholine, GABA, substance P, or serotonin itself. 5-HT3-receptor agonists cause unpleasant effects like nausea and anxiety, and no clinical use has been considered. In contrast, the introduction of 5-HT3-receptor antagonists for chemotherapy-induced vomiting was extremely successful. After development of other gastrointestinal indications like postoperative vomiting and diarrhea-predominant irritable bowel syndrome recent research focuses on rheumatological indications such as fibromyalgia, rheumatoid arthritis and tendinopathies. Positive effects have also been observed for pain syndromes such as chronic neuropathic pain and migraine. These effects seem to be related to substance P-mediated inflammation and hyperalgesia. Furthermore, antiinflammatory and immunomodulatory properties have been observed for 5-HT3-receptor antagonists which might explain promising findings in systemic sclerosis and other immunological conditions. For all of these innovative indications the optimal dosing schedule is a crucial issue, since a bell-shaped dose-response curve has been observed repeatedly for 5-HT3-receptor antagonists, particularly in CNS effects.
Collapse
Affiliation(s)
- Lothar Faerber
- Department of Pharmacology, Regensburg Medical School, Universitaetsstr. 31, 93053 Regensburg, Germany.
| | | | | | | | | |
Collapse
|
7
|
Alkadhi KA, Alzoubi KH, Aleisa AM, Tanner FL, Nimer AS. Psychosocial stress-induced hypertension results from in vivo expression of long-term potentiation in rat sympathetic ganglia. Neurobiol Dis 2005; 20:849-57. [PMID: 16005635 DOI: 10.1016/j.nbd.2005.05.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 05/10/2005] [Accepted: 05/17/2005] [Indexed: 12/11/2022] Open
Abstract
Long-term potentiation in sympathetic ganglia (gLTP) is an activity-dependent unique form of synaptic plasticity in that it is serotonin-dependent and can be completely inhibited by 5-HT3 receptor antagonists. Long lasting enhancement of the basal tone of ganglionic transmission seen with gLTP results in a sustained increase in peripheral resistance that leads to elevated blood pressure. We examined the possibility that, in sympathetic ganglia, stress-induced gLTP may be responsible for the expression of stress hypertension. Chronic treatment of male and female Wistar rats with a 5-HT3 receptor antagonist, tropisetron (ICS; 5 mg/kg/day) or ondansetron (0.5 mg/kg/day), prevented or reversed psychosocial stress-induced increases in blood pressure in stressed rats with no significant effect on blood pressure of unstressed control rats. Pharmacological and electrophysiological evidence that supports the presence of gLTP in ganglia isolated from stressed hypertensive rats includes inhibition of basal synaptic transmission by 5-HT3 antagonists, failure to induce gLTP with repetitive stimulation indicating occlusion of gLTP due to saturation and a left hand shift of the input/output curve. We suggest that a sustained stress-induced increase in central sympathetic efferent impulses to ganglia may provide the repeated high frequency presynaptic activity required to induce gLTP in sympathetic ganglia, thereby enhancing sympathetic tone to blood vessels resulting in hypertension.
Collapse
Affiliation(s)
- Karim A Alkadhi
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX 77204-5515, USA.
| | | | | | | | | |
Collapse
|
8
|
Yano S, Makino K, Nakamura H, Kai Y, Morioka M, Hamada JI, Kochi M, Kuratsu JI. Comparative Clinical Study of the Anti-Emetic Effects of Oral Ramosetron and Injected Granisetron in Patients With Malignant Glioma Undergoing ACNU Chemotherapy. Neurol Med Chir (Tokyo) 2005; 45:294-8; discussion 298-9. [PMID: 15973062 DOI: 10.2176/nmc.45.294] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effectiveness of ramosetron tablets and granisetron injection was compared for reducing the frequency of nausea, vomiting, and anorexia in patients with malignant glioma undergoing ACNU chemotherapy. Patients with malignant glioma to be treated with ACNU chemotherapy were randomly assigned to receive oral ramosetron (20 patients) or intravenous granisetron (19 patients) prior to ACNU injection. Gastrointestinal toxicity within 48 hours of ACNU injection was compared to that in patients who had received ACNU chemotherapy with dopamine D2 receptor-blocker as a historical control group. Within 24 hours of the administration of ACNU, 15 of the 20 patients treated with ramosetron and 16 of the 19 treated with granisetron were nausea-free, and 14 of the former and 14 of the latter regained their normal appetite. There was no significant difference in the anti-emetic effects. Ten of the 17 controls experienced no vomiting within 6 hours of the injection of ACNU, five were nausea-free within 24 hours, and two retained their normal appetite within 24 hours. Oral ramosetron has the same anti-anorectic and anti-emetic effects as intravenous granisetron. Ramosetron tablets are less expensive and are easy to take, so should be on the list of first-choice anti-emetic drugs for patients treated with ACNU chemotherapy.
Collapse
Affiliation(s)
- Shigetoshi Yano
- Department of Neurosurgery, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University Graduate School, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Abstract
Cytotoxic drug-induced nausea and vomiting are the side effects most feared by cancer patients. Emesis is an instinctive defense reaction caused by the somato-autonomic nerve reflex, which is integrated in the medulla oblongata. Emesis caused by anticancer drugs is associated with an increase in the concentration of serotonin (5-HT) (5-HT) in the intestinal mucosa and brainstem. 5-HT released from the enterochromaffin (EC) cells, which synthesize and secrete 5-HT, stimulates the 5-HT receptors on the adjacent vagal afferent nerves. The depolarization of the vagal afferent nerves stimulates the vomiting center in the brainstem and eventually induces a vomiting reflex. 5-HT released from EC cells appears to mediate the cisplatin-induced emesis sensitive to 5-HT(3) receptor antagonists. The precise role of 5-HT in the occurrence of vomiting has not been fully elucidated. The present review describes the role of 5-HT in anticancer drug-induced emesis from the viewpoint of 5-HT release and afferent vagal nerve activity. Various models and methods for predicting emesis are also evaluated.
Collapse
Affiliation(s)
- Masaru Minami
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan.
| | | | | | | |
Collapse
|
10
|
Fujii Y, Tanaka H. RETRACTED: Results of a prospective, randomized, double-blind, placebo-controlled, dose-ranging trial to determine the effective dose of ramosetron for the prevention of vomiting after tonsillectomy in children. Clin Ther 2003; 25:3135-42. [PMID: 14749151 DOI: 10.1016/s0149-2918(03)90097-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Postoperative vomiting (POV) is an important adverse effect of anesthesia and surgery, and children undergoing tonsillectomy may be particularly at risk. OBJECTIVE The aim of this study was to determine the effective dose of ramosetron, a 5-hydroxytryptamine type 3 receptor antagonist, for prophylaxis of severe POV (> or =2 episodes) in children undergoing general anesthesia for tonsillectomy. METHODS Standard general anesthetic technique and postoperative analgesia were used in this prospective, randomized, double-blind, placebo-controlled, dose-ranging trial of pediatric patients. Patients who had experienced POV, had taken an antiemetic medication within 24 hours before surgery of had a history of motion sickness were excluded. Only patients aged 4 to 10 years were included, because of their ability to answer questions. Patients received a single administration of either i.v. placebo or i.v. ramosetron at 3, 6, or 12 microg/kg immediately after the end of surgery. During the first 48 hours after anesthesia, episodes of retching, vomiting, and adverse events were recorded by nursing staff blinded to treatment assignment. RESULTS Eighty children (20 in each group)--42 girls and 38 boys--were enrolled. There were no differences in patient demographic characteristics among the treatment groups. The rates of complete response (no vomiting, retching, or need for another antiemetic medication) from 0 to 24 hours after anesthesia were 35% (7/20) with ramosetron 3 microg/kg, 90% (18/20) with ramosetron 6 micro/kg, and 90% (18/20) with ramosetron 12 microg/kg compared with placebo (30% [620], P=NS, P=0.001, and P=0.001 vs placebo, respectively); the corresponding rates from 24 to 48 hours after anesthesia were 35% (7/20), 90% (18/20), and 95% (19/20) compared with placebo (35% [7/20]; P=NS, P=0.001, and P=0.001 vs placebo, respectively). No difference in antiemetic efficacy was observed between ramosetron 6 and 12 microg/kg. No clinically serious adverse events attributable to the study drug were observed in any group. CONCLUSIONS In the pediatric population studied, ramosetron 6 microg/kg was effective for the prevention of vomiting after tonsillectomy from 0 to 48 hours after anesthesia. Increasing the dose to 12 microg/kg did not appear to provide further benefit.
Collapse
Affiliation(s)
- Yoshitaka Fujii
- Department of Anesthesiology, Toride Kyodo General Hospital, Toride City, Ibaraki, Japan.
| | | |
Collapse
|
11
|
Minami M, Endo T, Hirafuji M, Hamaue N, Liu Y, Hiroshige T, Nemoto M, Saito H, Yoshioka M. Pharmacological aspects of anticancer drug-induced emesis with emphasis on serotonin release and vagal nerve activity. Pharmacol Ther 2003; 99:149-65. [PMID: 12888110 DOI: 10.1016/s0163-7258(03)00057-3] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cytotoxic drug-induced nausea and vomiting are the side effects most feared by cancer patients. Emesis is an instinctive defense reaction caused by the somatoautonomic nerve reflex, which is integrated in the medulla oblongata. Emesis caused by cytotoxic drugs such as cisplatin is associated with an increase in the concentration of 5-hydroxytryptamine (5-HT) in the intestine and the brainstem. It is proposed that cytotoxic drugs evoke 5-HT release from the enterochromaffin (EC) cells in the intestinal mucosa and that the released 5-HT stimulates the 5-HT receptors on the adjacent vagal afferent nerves. The depolarization of the vagal afferent nerves stimulates the vomiting center in the brainstem and eventually induces a vomiting reflex. 5-HT released from EC cells seems to mediate the cisplatin-induced emesis sensitive to 5-HT(3) receptor antagonists. The release of 5-HT from the EC cells, however, is regulated by polymodal mechanisms on autoreceptors or heteroreceptors. The precise role of 5-HT on the occurrence of vomiting has not been fully elucidated. The present review aims to describe the role of 5-HT in anticancer drug-induced emesis from the viewpoint of 5-HT release and afferent vagus nerve activity. Various methods for predicting emesis are also evaluated.
Collapse
Affiliation(s)
- Masaru Minami
- Department of Pharmacology, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Kanazawa, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Fujii Y, Tanaka H. Comparison of granisetron and ramosetron for the prevention of nausea and vomiting after thyroidectomy. Clin Ther 2002; 24:766-72. [PMID: 12075944 DOI: 10.1016/s0149-2918(02)85150-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Postoperative nausea and vomiting (PONV) are common after thyroidectomy. Granisetron, a selective 5-hydroxytryptamine type 3 (5-HT3) receptor antagonist, is more effective than the traditional antiemetics droperidol and metoclopramide for the prevention of PONV after thyroidectomy. Ramosetron, another new selective antagonist of 5-HT3 receptor, has been shown to have more potent and longer-acting properties than granisetron against cisplatin-induced emesis in ferrets. OBJECTIVE This study was undertaken to compare the efficacy and tolerability of granisetron and ramosetron for the prevention of PONV after thyroidectomy. METHODS In this randomized, double-blind study, patients received granisetron 3 mg or ramosetron 0.3 mg intravenously at the end of surgery. A standard general anesthetic technique and postoperative analgesia were used. Emetic episodes and safety were assessed during the first 24 hours and the second 24 hours after anesthesia. RESULTS Eighty patients (15 men, 65 women) aged 33 to 58 years were included in the study. Each study group consisted of 40 patients. There were no differences between groups with regard to patient demographics. The percentage of patients who were emesis free (no nausea, no retching, no vomiting) 0 to 24 hours after anesthesia was 83% (33 of 40) with granisetron and 88% (35 of 40) with ramosetron; the corresponding rates 24 to 48 hours after anesthesia were 63% (25 of 40) and 90% (36 of 40), respectively (P = 0.004). The safety profile of the two 5-HT3 receptor antagonists was comparable, as no clinically serious adverse effects caused by the study drug were observed in either of the groups. CONCLUSIONS Prophylactic antiemetic therapy with ramosetron was comparable to therapy with granisetron for the prevention of PONV 0 to 24 hours after anesthesia in patients who underwent thyroidectomy; 24 to 48 hours after anesthesia, ramosetron was more ef- fective than granisetron for prophylaxis against PONV in this population.
Collapse
Affiliation(s)
- Yoshitaka Fujii
- Department of Anesthesiology, Toride Kyodo General Hospital, Toride City, Ibaraki, Japan.
| | | |
Collapse
|
13
|
Kang YK, Park YH, Ryoo BY, Bang YJ, Cho KS, Shin DB, Kim HC, Lee KH, Park YS, Lee KS, Heo DS, Kim SY, Cho EK, Lim HY, Kim WK, Lee JA, Kim TY, Lee JC, Yoon HJ, Kim NK. Ramosetron for the prevention of cisplatin-induced acute emesis: a prospective randomized comparison with granisetron. J Int Med Res 2002; 30:220-9. [PMID: 12166338 DOI: 10.1177/147323000203000302] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Control of nausea and vomiting is very important in determining patient compliance with cisplatin chemotherapy. A multicentre, randomized, single-blind study was conducted to compare the tolerability and efficacy of ramosetron with those of granisetron over 24 h following cisplatin administration to cancer patients. In eight study centres, a total of 194 adult patients were randomly assigned to receive either intravenous ramosetron 0.3 mg or intravenous granisetron 3.0 mg. The anti-emetic effect of ramosetron determined from the no-vomiting rate lasted longer, but there was no significant difference in the number of acute vomiting episodes or the severity of nausea between the two groups. In the tolerability evaluation, there were no statistically significant differences between the two groups, except for a higher incidence of dull headache in the granisetron group. Ramosetron and granisetron appear to have equivalent efficacy and tolerability profiles, but the effects of ramosetron on the prevention of acute vomiting in patients undergoing cisplatin chemotherapy were longer lasting.
Collapse
Affiliation(s)
- Y K Kang
- Department of Internal Medicine, Korea Cancer Centre Hospital, Seoul, Korea.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Patten D, Foxon GR, Martin KF, Halliwell RF. An electrophysiological study of the effects of propofol on native neuronal ligand-gated ion channels. Clin Exp Pharmacol Physiol 2001; 28:451-8. [PMID: 11380521 DOI: 10.1046/j.1440-1681.2001.03469.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Pharmacological evidence suggests that some of the clinical actions of propofol may be mediated, at least in part, by positive modulation of the GABA(A) receptor chloride channel. The effect of propofol at other native neuronal ligand-gated ion channels is unclear. 2. To gain some insight into the effects of propofol at a range of native neuronal receptors, the present study has used an extracellular recording technique and determined its effects at GABA(A), 5-HT3, P2X and nicotinic acetylcholine (nACh) receptors of the rat isolated vagus nerve and the GABA(A) and strychnine-sensitive glycine receptor of the rat isolated optic nerve. In addition, we have used patch-clamp recording techniques to further investigate the effects of propofol at the GABA(A) and strychnine-sensitive glycine receptors in rat cultured hippocampal neurons. 3. Propofol (0.3-100 micromol/L) concentration-dependently potentiated submaximal GABA-evoked responses in the vagus nerve and shifted the GABA concentration-response curve to the left. In contrast, propofol at concentrations ranging from 1 to 10 micromol/L had little or no effect on 5-HT3, P2X or nACh receptor-mediated responses in the vagus nerve but, at 100 micromol/L, propofol inhibited these responses to approximately 50% of control. In the optic nerve, EC20 GABA-evoked responses were also potentiated by propofol (10 micromol/L), while EC20 glycine-evoked responses were minimally enhanced. 4. Further investigations using cultured hippocampal neurons showed that submaximal (10 micromol/L) GABA-evoked currents were potentiated by propofol (1-10 micromol/L), in a non-voltage-dependent manner, whereas submaximal (100 micromol/L) glycine-evoked currents were unaffected. 5. These data suggest that propofol, at therapeutic concentrations, exerts its principle pharmacological actions at GABA(A) receptors with relatively little effect at other neuronal ligand-gated ion channels.
Collapse
MESH Headings
- Anesthetics, Intravenous/pharmacology
- Animals
- Cells, Cultured
- Electrophysiology
- Ion Channel Gating/drug effects
- Ligands
- Male
- Neurons/drug effects
- Neurons/metabolism
- Optic Nerve/cytology
- Optic Nerve/drug effects
- Patch-Clamp Techniques
- Propofol/pharmacology
- Rats
- Rats, Sprague-Dawley
- Rats, Wistar
- Receptors, Cholinergic/drug effects
- Receptors, Glycine/drug effects
- Receptors, Purinergic P2/drug effects
- Receptors, Serotonin/drug effects
- Receptors, Serotonin, 5-HT3
- Vagus Nerve/cytology
- Vagus Nerve/drug effects
- gamma-Aminobutyric Acid/pharmacology
Collapse
Affiliation(s)
- D Patten
- Department of Biological Sciences, Science Laboratories, University of Durham, Durham, United Kingdom
| | | | | | | |
Collapse
|
15
|
Abstract
To characterize the pharmacokinetics of protein-free granisetron in blood and brain we implanted microdialysis probes into the jugular vein and cerebral frontal cortex of the rat. Granisetron (3 or 6 mg/kg, i.v., n=6) was then administered, and microdialysates from blood and brain were collected from both sites and assayed by a validated high-performance liquid chromatographic method. Pharmacokinetics parameters were calculated from the corrected dialysate concentrations of granisetron versus time data. The elimination half-lives of granisetron in blood and brain were 51.3+/-5.5 and 69.7+/-6.3 min for 6 mg/kg, and 50.7+/-4.3 and 74.3+/-12.5 min for 3 mg/kg, respectively. Granisetron rapidly entered the extracellular fluid of cerebral frontal cortex at Tmax of 24 min. The results suggest that simultaneous microdialysis in blood and brain can be usefully applied to study the pharmacokinetics of granisetron in the periphery and the central nervous system.
Collapse
Affiliation(s)
- C T Huang
- Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | | | | |
Collapse
|
16
|
Jørgensen H, Knigge U, Kjaer A, Warberg J. Adrenocorticotropic hormone secretion in rats induced by stimulation with serotonergic compounds. hsj@mfi.ku.dk. J Neuroendocrinol 1999; 11:283-90. [PMID: 10223282 DOI: 10.1046/j.1365-2826.1999.00328.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The serotonin receptors involved in the secretion of adrenocorticotropin hormone (ACTH) were investigated in conscious adult male rats. Administration of serotonin (5-HT), 5-hydroxytryptophan (5-HTP) in combination with the serotonin reuptake inhibitor fluoxetine (Flx), or of the 5-HT agonists 8-OH-DPAT (5-HT1A), 5-carboxamido-tryptamine (5-HT1A+1B+5A+7), RU 24969 (5-HT1B+1A), DOI (5-HT2A+2c), S-alpha-methyl-5-HT (5-HT2A+2B+2c), MK212 (5-HT2B+2c), or methyl-chlorophenyl-piperazine (5-HT2A+2c) dose-dependently stimulated ACTH secretion. The 5-HT3 agonist 2-methyl-5-HT had no effect. Administration of a 5-HT1 agonist in combination with any of the 5-HT2 agonists DOI, S-alpha-methyl-5-HT or MK212 had an additive effect on the plasma concentration of ACTH. The ACTH stimulating effect of each of the 5-HT agonists was inhibited by pretreatment with antagonists with corresponding 5-HT receptor affinity. The ACTH response to 5-HT or 5-HTP/Flx was inhibited by injection with the 5-HT1A+2A+2c+5A+7 antagonist methysergide, the 5-HT2A antagonist ketanserine and the 5-HT2C+2A antagonist LY 53857. The 5-HT1A antagonist WAY 100635 enhanced 5-HT- and 5-HTP/Flx-induced ACTH secretion, suggesting a presynaptic 5-HT1A autoreceptor effect of the drug. The 5-HT3 antagonist ondansetrone had no effect on the either of the 5-HT agonists. The 5-HT3+4 antagonist tropisetrone attenuated the effect of 5-HTP/Flx, which may suggest a stimulation of ACTH secretion via 5-HT4 receptors. It is concluded that 5-HT1A, 5-HT2A+2C, and to a lesser extent 5-HT1B receptors, but not 5-HT3 receptors are involved in the effects of serotonin agonists on ACTH secretion. Furthermore, an involvement of the 5-HT5A and the 5-HT7 receptor is possible.
Collapse
Affiliation(s)
- H Jørgensen
- Department of Medical Physiology, The Panum Institute, University of Copenhagen, Denmark.
| | | | | | | |
Collapse
|
17
|
Jørgensen H, Knigge U, Kjaer A, Vadsholt T, Warberg J. Serotonergic involvement in stress-induced ACTH release. Brain Res 1998; 811:10-20. [PMID: 9804868 DOI: 10.1016/s0006-8993(98)00901-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We investigated the involvement of serotonin (5-HT) and 5-HT receptors in mediation of stress-induced ACTH secretion in adult male rats, which were pretreated by 5-HT antagonists before restraint-, ether-, cold swim-stress or endotoxin. All stressors potently increased plasma ACTH. Lesion of 5-HT neurons with 5, 7-dihydroxytryptamine injected intracerebroventricularly, into the paraventricular nucleus or into the raphe nuclei, inhibited the restraint stress-induced ACTH response by 50%. Restraint increased the content of 5-HT and its metabolite 5-hydroxyindole acetic acid, in the raphe nuclei, whereas the other stressors had no such effect. Pretreatment with the 5-HT1A receptor antagonist WAY 100635 inhibited the restraint stress- and endotoxin-induced ACTH secretion by 50%. The 5-HT1+2 antagonist methysergide or the 5-HT2 antagonist ketanserin inhibited the restraint- or ether stress-induced ACTH response, and eliminated the endotoxin-induced ACTH response. The 5-HT2 receptor antagonist LY 53857 blocked only the endotoxin-induced ACTH response. Pretreatment with the 5-HT3 receptor antagonist ondansetrone had no effect on stress-stimulated ACTH secretion. The 5-HT3+4 receptor antagonist tropisetrone inhibited the restraint- and ether stress-induced response. The ACTH response to swim stress was not affected by any of the antagonists used. It is concluded that the 5-HT1A, the 5-HT2A and the 5-HT2C receptor, but not the 5-HT3 receptor are involved in the stress-induced ACTH secretion. An involvement of the 5-HT4 receptor is possible. Furthermore, that serotonergic neurons in the raphe nuclei are activated during restraint stress, and that these neurons and neurons in PVN of the hypothalamus, are important for the mediation of the restraint stress-induced ACTH response.
Collapse
Affiliation(s)
- H Jørgensen
- Department of Medical Physiology, The Panum Institute 12.3, University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen N, Denmark.
| | | | | | | | | |
Collapse
|
18
|
Fletcher S, Barnes NM. Desperately seeking subunits: are native 5-HT3 receptors really homomeric complexes? Trends Pharmacol Sci 1998; 19:212-5. [PMID: 9666711 DOI: 10.1016/s0165-6147(98)01210-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The 5-HT3 receptor complex is a ligand-gated ion channel, and is therefore likely to comprise multiple subunits in common with other members of this superfamily. To date, however, only one 5-HT3 receptor subunit, plus an alternatively spliced variant, have been identified. In this article, Stephanie Fletcher and Nicholas Barnes review some of the extensive data in the literature that suggest the presence of other 5-HT3 receptor subunits. This is particularly relevant given the recent demonstration that the 5-HT3 receptor purified from pig brain contains a non-5-HT3A-like protein(s).
Collapse
Affiliation(s)
- S Fletcher
- Department of Pharmacology, Medical School, University of Birmingham, Edgbaston, UK
| | | |
Collapse
|
19
|
Hewlett WA, Schmidt DE, Mason NS, Trivedi BL, Ebert MH, de Paulis T. Synthesis and 5-HT-3 receptor binding of 2- and 3-(halo)alkoxyl substituted (S)-N-(1-azabicyclo[2.2.2]oct-3-yl)-5-chlorobenzamides as potential radioligands. Nucl Med Biol 1998; 25:141-53. [PMID: 9468029 DOI: 10.1016/s0969-8051(97)00161-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In an effort to develop selective, high-affinity radioligands for the 5-HT-3 receptor, a series of homologues of 5-chloro-2,3-dimethoxy-N-(1-azabicyclo[2.2.2]oct-3-yl)benzamide (2b) was prepared in which individual methoxy groups were replaced by ethoxyl, (2-fluoroethoxyl), allyloxyl, propargyloxyl, or (3-iodoallyl)oxyl groups. Affinities for the 5-HT-3 receptor were determined by displacement of the binding of [125I]MIZAC (2a), a selective 5-HT-3 receptor antagonist radioligand, in rat brain homogenates. The 3-substituted homologues were more potent than the lead compound, 2b. The homologue having the largest 3-substituent, i.e., E-(S)-N-(1-azabicyclo[2.2.2]oct-3-yl)-5-chloro-3-(3-iodo-2-propenyl)oxy- 2-methoxybenzamide (3b, THIZAC), had one of the highest affinities, Ki 0.08 nM. The 2-substituted homologues were equipotent with 2b, having Ki 0.2-0.3 nM, regardless of the size of the substituent. The corresponding iodoallyl derivative, E-(S)-N-(1-azabicyclo[2.2.2]oct-3-yl)-5-chloro-2-(3-iodo-2-propenyl)oxy- 3-methoxybenzamide (4, LIZAC), displayed a Ki of 0.29 nM. Saturation binding of [125I]-4 gave a KD of 0.31 +/- 0.04 nM and a Bmax of 2.36 +/- 0.10 fmol/mg of entorhinal cortex. In vivo biodistribution of [125I]-4 in the rat brain showed increased accumulation in hippocampus relative to that in cerebellum. Both the high-affinity ligands [125I]-3b and [125I]-4 are potentially useful radioligands for studying the 5-HT-3 receptor.
Collapse
Affiliation(s)
- W A Hewlett
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | | | | | | | | | | |
Collapse
|
20
|
López-Rodríguez ML, Morcillo MJ, Benhamú B, Rosado ML. Comparative receptor mapping of serotoninergic 5-HT3 and 5-HT4 binding sites. J Comput Aided Mol Des 1997; 11:589-99. [PMID: 9491351 DOI: 10.1023/a:1007908707650] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The clinical use of currently available drugs acting at the 5-HT4 receptor has been hampered by their lack of selectivity over 5-HT3 binding sites. For this reason, there is considerable interest in the medicinal chemistry of these serotonin receptor subtypes, and significant effort has been made towards the discovery of potent and selective ligands. Computer-aided conformational analysis was used to characterize serotoninergic 5-HT3 and 5-HT4 receptor recognition. On the basis of the generally accepted model of the 5-HT3 antagonist pharmacophore, we have performed a receptor mapping of this receptor binding site, following the active analog approach (AAA) defined by Marshall. The receptor excluded volume was calculated as the union of the van der Waals density maps of nine active ligands (pKi > or = 8.9), superimposed in pharmacophoric conformations. Six inactive analogs (pKi < 7.0) were subsequently used to define the essential volume, which in its turn can be used to define the regions of steric intolerance of the 5-HT3 receptor. Five active ligands (pKi > or = 9.3) at 5-HT4 receptors were used to construct an antagonist pharmacophore for this receptor, and to determine its excluded volume by superimposition of pharmacophoric conformations. The volume defined by the superimposition of five inactive 5-HT4 receptor analogs that possess the pharmacophoric elements (pKi < or = 6.6) did not exceed the excluded volume calculated for this receptor. In this case, the inactivity may be due to the lack of positive interaction of the amino moiety with a hypothetical hydrophobic pocket, which would interact with the voluminous substituents of the basic nitrogen of active ligands. The difference between the excluded volumes of both receptors has confirmed that the main difference is indeed in the basic moiety. Thus, the 5-HT3 receptor can only accommodate small substituents in the position of the nitrogen atom, whereas the 5-HT4 receptor requires more voluminous groups. Also, the basic nitrogen is located at ca. 8.0 A from the aromatic moiety in the 5-HT4 antagonist pharmacophore, whereas this distance is ca. 7.5 A in the 5-HT3 antagonist model. The comparative mapping of both serotoninergic receptors has allowed us to confirm the three-component pharmacophore accepted for the 5-HT3 receptor, as well as to propose a steric model for the 5-HT4 receptor binding site. This study offers structural insights to aid the design of new selective ligands, and the resulting models have received some support from the synthesis of two new active and selective ligands: 24 (Ki(5-HT3) = 3.7 nM; Ki(5-HT4) > 1000 nM) and 25 (Ki(5-HT4) = 13.7 nM; Ki(5-HT3) > 10,000 nM).
Collapse
Affiliation(s)
- M L López-Rodríguez
- Departamento de Química Orgánica I, Facultad de Ciencias, Químicas, Universidad Complutense, Madrid, Spain
| | | | | | | |
Collapse
|
21
|
Abstract
1. We demonstrate, for the first time, the purification of the 5-hydroxytryptamine3 (5-HT3) receptor from a native tissue source, pig cerebral cortex. 2. From a range of detergents, the non-ionic detergent Triton X-100 was demonstrated to exhibit the least inhibition of [3H]-(S)-zacopride binding to membrane bound 5-HT3 receptors from pig cerebral cortex at concentrations above its critical micellular concentration (CMC). This detergent was therefore selected to solubilize 5-HT3 binding sites from homogenates of pig cerebral cortex. Maximum yield (43.8 +/- 3.7%, mean +/- s.e.mean, n = 13) was obtained with Triton X-100 at 0.4% (22.1 x CMC). Radioligand binding studies with [3H]-(S)-zacopride indicated that the solubilized 5-HT3 receptor displayed near identical pharmacology to the membrane bound receptor (the correlation coefficient (r) between the pKi values of structurally unrelated compounds competing for [3H]-(S)-zacopride binding in the membrane bound and solubilized 5-HT3 receptor preparations was 0.99, Bmax = 20.7 +/- 4.2 fmol mg(-1) protein, Kd = 1.57 +/- 0.53 nM, mean +/- s.e.mean, n = 6). 3. Solubilized (0.4% Triton X-100) 5-HT3 receptors were affinity purified using Affi-Gel 15 coupled to the high affinity 5-HT3 receptor ligand GR119566X. Radioligand binding studies indicated that the pharmacological profile of the affinity purified 5-HT3 receptor, assessed using ligands with a range of affinities spanning 3 orders of magnitude, was similar to that in both crude homogenates (r = 0.85) and solubilized 5-HT3 receptor sites (r = 0.85) from pig brain. The specific activity for the purified 5-HT3 receptor overlapped the theoretical specific activity of the receptor (Bmax = 3.27 +/- 1.41 and 5.35 +/- 2.33 nmol mg(-1) protein, assessed by saturation and competition studies respectively, mean +/- s.e.mean, n = 3-4), which indicated a 60000-100000 fold purification of the membrane bound receptor. 4. Under non-reducing conditions, samples of the affinity purified protein failed to enter a 10% separating gel in SDS-PAGE analysis, indicating a molecular mass for the receptor complex of > 200 kDa. Further investigation of the non-reduced purified protein with a 7.5% separating gel gave a mass for the complex of approximately 279 kDa. Under reducing conditions, SDS-PAGE analysis of the affinity purified 5-HT3 receptor resulted in 3-6 silver stained bands at apparent molecular masses of 37, 44-50, 52, 57-61, 63 and 65-71 kDa (n = 12). Unlike protein bands at 45, 50, 60 and 66 kDa, the bands corresponding to proteins of 52, 57, 63 and 71 kDa consistently gave no reaction with an antiserum specific for the cloned A subunit of the 5-HT3 receptor in both a modified dot blot procedure and a Western blot procedure (n = 2-5). 5. We conclude that we have purified the 5-HT3 receptor from pig brain to homogeneity and suggest this may contain non-5-HT3-A receptor subunit(s).
Collapse
Affiliation(s)
- S Fletcher
- Department of Pharmacology, The Medical School, University of Birmingham, Edgbaston
| | | |
Collapse
|
22
|
Nagakura Y, Ito H, Kamato T, Nishida A, Miyata K. Effect of a selective 5-HT3 receptor agonist on gastric motility in fasted and fed dogs. Eur J Pharmacol 1997; 327:189-93. [PMID: 9200559 DOI: 10.1016/s0014-2999(97)89660-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of m-chlorophenylbiguanide, a selective 5-HT3 receptor agonist, on gastric antral motility was investigated in conscious dogs with a force transducer implanted chronically. m-Chlorophenylbiguanide (0.1-1 mg/kg i.v.) dose dependently enhanced antral motility in the fasted state, and the amplitude of m-chlorophenylbiguanide (1 mg/kg i.v.)-induced antral contractions reached the level of natural phase III contractions. In contrast, m-chlorophenylbiguanide reduced the amplitude of antral contractions in the fed state. A selective 5-HT3 receptor antagonist, ramosetron (0.0003-0.03 mg/kg i.v.), inhibited both effects of m-chlorophenylbiguanide. m-Chlorophenylbiguanide (1 mg/kg i.v.)-induced contractions were inhibited by atropine (0.03 or 0.1 mg/kg i.v.). These results indicate that pharmacological activation of 5-HT3 receptors has opposite effects on canine gastric antral motility in the fasted and in the fed state, being stimulatory and inhibitory, respectively. The stimulatory effect seems to be mediated mainly via the release of acetylcholine.
Collapse
Affiliation(s)
- Y Nagakura
- Pharmacological Laboratories, Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co. Ltd., Tsukuba, Ibaraki, Japan.
| | | | | | | | | |
Collapse
|
23
|
Synthesis and 5-HT-3 receptor binding activity of 5-[125I]iodo-2,3-dimethoxy-N-(1-azabicyclo[2.2.2]oct-3-yl)benzamide and its 5-halogen-2-alkoxyl homologues. Eur J Med Chem 1997. [DOI: 10.1016/s0223-5234(97)81676-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
24
|
Kiso T, Ito H, Miyata K. Effect of ramosetron on short-circuit current response in rat colonic mucosa. Eur J Pharmacol 1997; 320:187-92. [PMID: 9059853 DOI: 10.1016/s0014-2999(96)00893-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We investigated the effects of ramosetron (YM060, (-)-(R)-5-[(1-methyl-1H-indol-3-yl)carbonyl]-4,5,6,7-tetrahydro-1 H-benzimidazole monohydrochloride) on the short-circuit current (Isc) responses to 5-HT receptor agonists in the rat distal colon, and compared its potency to that of other 5-HT3 receptor antagonists. 5-Hydroxytryptamine (5-HT) concentration-dependently increased Isc. The Isc response to 5-HT was partially reduced by tetrodotoxin and ramosetron, and strongly inhibited by GR113808 ([[1-[(2-methyl-sulphonyl) amino]ethyl]-4-piperidin-yl]methyl 1-methyl-1 H-indole-3-carboxylate). 2-Methyl-5-HT and 5-methoxytryptamine also increased Isc. The former response was inhibited by ramosetron, and the latter was abolished by GR113808. Ramosetron, YM114 (KAE-393, (-)-(R)-5-[(1-indolinyl)carbonyl]-4,5,6,7-tetrahydro-1 H-benzimidazole monohydrochloride) and granisetron concentration-dependently antagonized the Isc responses to 2-methyl-5-HT with reduction in the maximal response at higher concentrations. Apparent pA2 values for these antagonists were 10.40, 10.37 and 8.99, respectively. Ondansetron produced clear rightward shifts of the concentration-response curves to 2-methyl-5-HT, with a pA2 value of 8.53. These results suggest that 5-HT increases Isc through the 5-HT3 and 5-HT4 receptors, and that ramosetron is a potent and selective 5-HT3 receptor antagonist in rat colonic mucosa.
Collapse
Affiliation(s)
- T Kiso
- Pharmacology Laboratories, Yamanouchi Pharmaceutical Co., Ltd., Ibaraki, Japan
| | | | | |
Collapse
|
25
|
Yamano M, Ito H, Kamato T, Miyata K. Characteristics of inhibitory effects of serotonin (5-HT)3-receptor antagonists, YM060 and YM114 (KAE-393), on the von Bezold-Jarisch reflex induced by 2-Methyl-5-HT, veratridine and electrical stimulation of vagus nerves in anesthetized rats. JAPANESE JOURNAL OF PHARMACOLOGY 1995; 69:351-6. [PMID: 8786638 DOI: 10.1254/jjp.69.351] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We evaluated the inhibitory effects of YM060 [(R)-5-[(1-methyl-1H-indol- 3-yl)carbonyl]-4,5,6,7-tetrahydro-1H-benzimidazole monohydrochloride] and YM114 (KAE-393) [(R)-5-[(1-indolinyl)carbonyl]-4,5,6,7-tetrahydro-1H- benzimidazole monohydrochloride] on the von Bezold-Jarisch reflex (BJR) induced by 2-methyl-5-HT, a selective serotonin (5-HT)3-receptor agonist; veratridine, which stimulates chemoreceptors and baroreceptors; and electrical stimulation of vagal efferent nerves in anesthetized rats. Results were compared with those of ondansetron and granisetron. 2-Methyl- 5-HT (5-160 micrograms/kg, i.v.) and veratridine (100-200 micrograms/kg, i.v.) dose-dependently decreased the heart rate (BJR). YM060, YM114, ondansetron and granisetron dose-dependently inhibited 2-methyl-5-HT (40 micrograms/kg, i.v.)-induced BJR, with ID50 values of 0.012, 0.060, 0.97 and 0.15 microgram/kg, i.v., respectively. Their 5-HT3 receptor blocking potencies against 2-methyl-5-HT-induced BJR were largely consistent with those against 5-HT-induced BJR. In contrast, higher doses (100 micrograms/kg, i.v.) of YM060, YM114, ondansetron and granisetron did not inhibit veratridine (150 micrograms/kg, i.v.)-induced BJR. Atropine (300 micrograms/kg, i.v.) abolished bradycardia induced by electrical stimulation of vagal efferent nerves, whereas YM060, YM114, ondansetron and granisetron had no effect at a dose of 1000 micrograms/kg, i.v. 5-HT (0.625-5.0 micrograms) injected into the left ventricle also caused a dose-dependent decrease in heart rate, an effect that was abolished by YM060 (0.1 microgram/kg, i.v.), atropine (100 micrograms/kg, i.v.) and vagotomy. These results suggest that YM060 and YM114 are highly potent and selective 5-HT3-receptor antagonists that do not affect veratridine- or electrical stimulation-induced bradycardia in anesthetized rats. They also suggest that 5-HT-induced BJR in anesthetized rats originates from 5-HT3 receptors located on the endings of vagal afferent nerves in the heart.
Collapse
Affiliation(s)
- M Yamano
- Neuroscience and Gastrointestinal Research Laboratories, Yamanouchi Pharmaceutical Co., Ltd., Ibaraki, Japan
| | | | | | | |
Collapse
|
26
|
Miyata K, Yamano M, Kamato T, Akuzawa S. Effect of serotonin (5-HT)3-receptor antagonists YM060, YM114 (KAE-393), ondansetron and granisetron on 5-HT4 receptors and gastric emptying in rodents. JAPANESE JOURNAL OF PHARMACOLOGY 1995; 69:205-14. [PMID: 8699628 DOI: 10.1254/jjp.69.205] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We investigated the effects of YM060 [(R)-5-[(1-methyl-3-indolyl)carbonyl]-4,5,6,7-tetrahydro-1H-benzimidazol e hydrochloride] and YM114 (KAE-393) [(R)-5-[(2,3-dihydro-1-indolyl)-carbonyl]-4,5,6,7-tetrahydro-1H- benzimidazole hydrochloride] on 5-HT4 receptors and gastric emptying in normal and cisplatin-treated rats and compared results with those for ondansetron and granisetron. YM060, YM114, ondansetron and granisetron dose-dependently inhibited the specific binding of [3H]-GR113808 ([[1-[(2-methylsulphonyl)amino]ethyl]-4-piperidin-yl]methyl 1-methyl-1H-indole-3-carboxylate) in guinea pig striatum, with pKi values of 5.53, 5.13, 5.21 and 5.63, respectively. According to the pKi values reported in 5-HT3-receptor binding of [3H]GR65630 to rat cortical membranes, the affinity of YM060, YM114, ondansetron and granisetron for 5-HT4 receptors was approximately 5, 5, 3.5 and 3.5 log units lower than that for 5-HT3 receptors, respectively. In the guinea pig longitudinal muscle with myenteric plexus and rat esophageal tunica muscularis mucosae, YM060 and YM114 showed neither 5-HT4-agonistic nor antagonistic properties. Although ondansetron produced concentration-dependent increases in the magnitude of the twitch response in longitudinal muscle, it did not possess 5-HT3- and 5-HT4-agonistic activity. Granisetron antagonized 5-HT-induced relaxation of the rat esophagus with an apparent pA2 value of 5.39. Intravenous YM060, YM114, ondansetron and granisetron significantly enhanced gastric emptying of glass beads and improved cisplatin-induced slowing of gastric emptying in rats. These results indicate that the selectivity of YM060 and YM114 for 5-HT3 receptors is higher than that of ondansetron and granisetron and that these 5-HT3 antagonists have gastroprokinetic activity in normal and cisplatin-treated rats without affecting 5-HT4 receptors.
Collapse
Affiliation(s)
- K Miyata
- Neuroscience Research Laboratory, Yamanouchi Pharmaceutical Co., Ltd., Ibaraki, Japan
| | | | | | | |
Collapse
|
27
|
Ito H, Tamura K. Inhibitory effect of YM060 on 5-HT3 receptor-mediated depolarization in colonic myenteric neurons of the guinea pig. Eur J Pharmacol 1995; 283:107-12. [PMID: 7498299 DOI: 10.1016/0014-2999(95)00296-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We used conventional intracellular recording methods to examine the effects of YM060 [(-)-(R)-5-[(1-methyl-1H-indol-3-yl)carbonyl]-4,5,6,7- tetrahydro-1H-benzimidazole monohydrochloride), a novel 5-HT3 receptor antagonist, on 5-hydroxytryptamine (5-HT, serotonin)-evoked fast membrane depolarization in myenteric neurons of the guinea pig distal colon, and compared its potency to that of other 5-HT3 receptor antagonists. Microapplication of 5-HT from fine-tipped pipettes evoked both fast and slowly activating depolarizing responses in 78% and 40% of colonic myenteric neurons, respectively. The selective 5-HT3 receptor agonist 2-methyl-5-HT applied with short pressure pulses (100-300 ms) mimicked the fast but not the slow response. The 5-HT3 receptor antagonists YM060, granisetron and ondansetron suppressed the 5-HT-evoked fast response in 98% of colonic myenteric neurons in a concentration-dependent manner with pIC50 values of 8.62, 7.77 and 6.90, respectively. Methysergide and GR113808 did not affect the fast responses at concentrations sufficient to block 5-HT1, 5-HT2 and 5-HT4 receptors, respectively. YM060 did not affect the slowly activating response to 5-HT or any other electrophysiological parameter of the neurons including resting membrane potential, input resistance and the amplitude of action potentials evoked by injection of depolarizing current. Stimulus-evoked fast excitatory postsynaptic potentials were unchanged by YM060 at concentrations up to 10(-8) M, excluding any possible local anesthetic or anticholinergic effects of YM060. The results confirm that the fast component of the two depolarizing responses to 5-HT in colonic myenteric neurons is mediated by 5-HT3 receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- H Ito
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., Tsukuba, Japan
| | | |
Collapse
|