Five different muscarinic receptor subtypes can be distinguished by the differences in their amino acid sequence, the coupled signal transduction system, pharmacological binding properties and activation of ionic fluxes. The present study served to characterize the binding profile of muscarinic receptors in human colon carcinoma cells (HT-29) using selective muscarinic antagonists. The affiniti...

Major pelvic ganglion electrocautery (MPGE) and spinal cord injury in the rat induce bladder hypertrophy and a change in muscarinic receptor subtypes mediating bladder contraction from predominantly M3 to a combination of M2 and M3. To determine whether this is a result of bladder hypertrophy or denervation, we studied the following groups: sham-operated controls, urinary diversion (DIV), MPGE ...

We investigated the coupling of muscarinic receptor (M) subtypes to phosphoinositide hydrolysis in ileum and urinary bladder using muscarinic receptor knockout mice. In urinary bladder from wild-type mice, the muscarinic agonist oxotremorine-M, elicited a robust phosphoinositide response characterized by an EC50 value of 0.22 microM and a maximal response (Emax) of 32.8% conversion of [3H]inosi...

OBJECTIVES No clinical disorders have been caused by dysfunction of any of the 5 subtypes (M1-M5) of muscarinic receptors. We present a patient with a novel clinical syndrome that we suggest results from a deficiency of the muscarinic M3 receptor. METHODS We conducted a comprehensive workup of autonomic function. The patient's disorder was compared to the phenotypic features of male M3 knocko...

Muscarinic acetylcholine receptors, which comprise five subtypes (M1-M5 receptors), are expressed in both the CNS and PNS (particularly the target organs of parasympathetic neurons). M1-M5 receptors are integral membrane proteins with seven transmembrane segments, bind with acetylcholine (ACh) in the extracellular phase, and thereafter interact with and activate GTP-binding regulatory proteins ...

Cholinergic modulation of synaptic transmission is vital to memory processes and may be responsible for setting network dynamics in the hippocampus appropriate for encoding of information. found evidence suggesting M1 receptors cause presynaptic inhibition of glutamatergic transmission, while research supports a role of the M2 receptor. We examined muscarinic inhibition of fEPSPs in stratum rad...

Cholinergic tone contributes to airflow obstruction in chronic obstructive pulmonary disease. Accordingly, anticholinergics are effective bronchodilators by blocking the muscarinic M3 receptor on airway smooth muscle. Recent evidence indicates that acetylcholine also contributes to airway inflammation. However, which muscarinic receptor subtype(s) regulates this process is unknown. In this stud...

OBJECTIVES This study examines whether M(2) receptors contribute to direct contraction of the detrusor in human neurogenic and idiopathic overactive bladders. METHODS Control detrusor muscle was obtained from patients undergoing cystectomy for bladder cancer, whilst overactive detrusor muscle was obtained from patients undergoing clam cystoplasty for idiopathic or neurogenic detrusor overacti...

The role of muscarinic receptors in several diseases including cancer has recently emerged. To evaluate the hypothesis that muscarinic acetylcholine receptors may play a role in bladder cancer as well as in other tumor types, we investigated their expression in bladder tumor specimens. All examined samples expressed the M1, M2 and M3 receptor subtypes. We also found that the level of M2 transcr...

Muscarinic acetylcholine signalling plays major roles in regulation of consciousness, cognitive functioning, pain perception and circulatory homeostasis. Halothane has been shown to inhibit m1 muscarinic signalling. However, no comparative data are available for desflurane, sevoflurane or isoflurane, nor have the anaesthetic effects on the m3 subtype (which is also prominent in the brain) been ...