The lack of utility of the rat vas deferens as a functional bioassay for sigma ligands.

Eur J Pharmacol

Department of Pharmacology, Organon Laboratories Limited, Newhouse, Lanarkshire, U.K.

Published: February 1991

The present study examined the utility of the rat vas deferens preparation as a bioassay for sigma site ligands. sigma Ligands such as (+/-)-pentazocine, phencyclidine (PCP) and (+)-SK&F 10047 potentiated neurogenic twitch contractions. However, neither the order of potency nor the absolute potency of (+/-)-pentazocine and (+)-SK&F 10047 correlated with their affinity at central sigma sites. Furthermore, another potent sigma ligand, ditolyl-ortho guanidine (DTG) neither affected neurogenic twitch contractions nor inhibited twitch potentiation by PCP or (+)-SK&F 10047 at concentrations up to 30 mumol/l. These data indicate that the rat vas deferens is not a useful bioassay for the evaluation of sigma ligands. PCP, (+)-SK&F 10047 and (+/-)-pentazocine probably enhance neurogenic contractions in rat vas deferens primarily by inhibition of the neuronal uptake of noradrenaline.

Download full-text PDF

Source
http://dx.doi.org/10.1016/0014-2999(91)90028-oDOI Listing

Publication Analysis

Top Keywords

rat vas
16
vas deferens
16
+-sk&f 10047
16
sigma ligands
12
pcp +-sk&f
12
utility rat
8
bioassay sigma
8
neurogenic twitch
8
twitch contractions
8
sigma
6

Similar Publications

Haemorrhoids are a common anorectal disease primarily treated through surgery, often leading to complications such as pain. The efficacy of acupuncture in relieving postoperative pain in mixed haemorrhoids has not been well-documented. This study included 90 patients undergoing haemorrhoid surgery and their Visual Analogue Score (VAS), inflammatory factor levels, Hamilton Depression Rating Scale (HAMD), and analgesic drug use were accessed.

View Article and Find Full Text PDF

Left superior cervical ganglia lymph node mimicry and its role in rat ventricular arrhythmias following myocardial infarction.

Acta Physiol (Oxf)

February 2025

Department of Cardiology, Cheeloo College of Medicine, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, China.

Aim: Sympathetic overactivation may lead to severe ventricular arrhythmias (VAs) post-myocardial infarction (MI). The superior cervical ganglion (SCG) is an extracardiac sympathetic ganglion which regulates cardiac autonomic tone. We aimed to investigate the characteristics and functional significance of SCG on neuro-cardiac communication post-MI.

View Article and Find Full Text PDF

Background: 6-Nitrodopamine (6-ND) released from rat vas deferens acts an endogenous modulator of vas deferens contractility.

Objectives: To investigate whether rat isolated seminal vesicles (RISV) releases 6-ND, the mechanisms involved in the release, and the modulatory role of 6-ND on tissue contractility.

Methods: Rat seminal vesicles were removed and placed in Krebs-Henseleit's solution at 37°C for 30 min, and an aliquot was used to analyze the concentrations of 6-ND, dopamine, noradrenaline, and adrenaline by liquid chromatography with tandem mass spectrometry (LC-MS/MS).

View Article and Find Full Text PDF

Puerarin reduces susceptibility to ventricular arrhythmias and inhibits ferroptosis via Sirt1/Nrf2 signaling in high-fat-diet rats.

Free Radic Biol Med

February 2025

State Key Laboratory of Bioactive Substances and Function of Natural Medicine, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, 100050, Beijing, China. Electronic address:

Obesity is a significant risk factor for cardiac arrhythmias, and the ferroptosis is closely related to cardiac arrhythmias. This study aimed to investigate whether puerarin (Pue), a natural isoflavone, could reduce the susceptibility to ventricular arrhythmias (VAs) associated with obesity and inhibit ferroptosis, with a particular focus on the Sirt1/Nrf2 signaling pathway. Male rats were randomly divided into three groups: normal chow diet (NC), high-fat diet (HFD), and HFD with Pue treatment (100mg/kg, HFD + Pue).

View Article and Find Full Text PDF

Treatment of patients with myocardial ischemic diseases crucially involves cardiac reperfusion (CR). However, oxidative stress and tissue lesions caused by CR may also lead to lethal complications, such as arrythmias and vasoplegic syndrome (VS). Although methylene blue (MB) has long been used to treat VS due to cardiac ischemia and reperfusion (CIR) and/or surgery because of its vascular effects, MB's effects on the heart are unclear.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!