piperidines and Neurogenic-Bowel

To analyze the use of alvimopan, a peripheral mu-opioid receptor antagonist, in expediting gastrointestinal recovery after benign abdominal urinary tract reconstruction. Alvimopan use has been well defined in the management of radical cystectomy and urinary diversion for oncologic indications. It has not been studied in benign abdominal genitourinary reconstruction.. Patients who underwent urinary reconstruction utilizing harvested bowel segments for benign conditions from 12/2014-7/2019 were retrospectively reviewed. From 5/2018-7/2019 our institution approved the use of perioperative alvimopan in the aforementioned patients (N = 11), who were paired 1:2 with patients from a cohort of alvimopan-eligible patients who did not receive the drug (N = 22). Patients were paired by (1) type of reconstruction and (2) presence of neurogenic bowel-bladder (NBB).. Of the 70 patients who underwent urinary reconstruction during the study period, 46 patients (66%) were eligible to receive alvimopan. Length of stay was shorter for the alvimopan group compared to the non-alvimopan group (median 5 days [IQR 4-5 days] vs. 8 days [IQR 6-11 days]; P = 0.002). Time to first bowel movement was shorter for the alvimopan group (median 4 days [IQR 3-4 days] vs. 6 days [IQR 4-7], P = 0.001). No patient treated with alvimopan required a nasogastric (NG) tube for post-operative ileus compared to 7 (32%) patients in the non-treatment group (P = 0.035). Post-operative complications and 30-day readmissions were similar between the two groups.. The use of perioperative alvimopan in benign abdominal urinary tract reconstruction expedited return of bowel function and decreased length of stay compared to a matched cohort of untreated patients.

Topics: Adult; Aged; Case-Control Studies; Female; Gastrointestinal Agents; Gastrointestinal Tract; Humans; Male; Middle Aged; Neurogenic Bowel; Piperidines; Recovery of Function; Retrospective Studies; Treatment Outcome; Urinary Bladder, Neurogenic; Urologic Diseases; Urologic Surgical Procedures

We tested the novel hypothesis that endogenous adenosine (eADO) activates low-affinity A3 receptors in a model of neurogenic diarrhea in the guinea pig colon. Dimaprit activation of H2 receptors was used to trigger a cyclic coordinated response of contraction and Cl(-) secretion. Contraction-relaxation was monitored by sonomicrometry (via intracrystal distance) simultaneously with short-circuit current (I(sc), Cl(-) secretion). The short interplexus reflex coordinated response was attenuated or abolished by antagonists at H2 (cimetidine), 5-hydroxytryptamine 4 receptor (RS39604), neurokinin-1 receptor (GR82334), or nicotinic (mecamylamine) receptors. The A1 agonist 2-chloro-N(6)-cyclopentyladenosine (CCPA) abolished coordinated responses, and A1 antagonists could restore normal responses. A1-selective antagonists alone [8-cyclopentyltheophylline (CPT), 1,3-dipropyl-8-(2-amino-4-chlorophenyl)xanthine (PACPX), or 8-cyclopentyl-N(3)-[3-(4-(fluorosulfonyl)benzoyloxy)propyl]-xanthine (FSCPX)] caused a concentration-dependent augmentation of crypt cell secretion or contraction and acted at nanomolar concentrations. The A3 agonist N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) abolished coordinated responses and the A3 antagonist 3-ethyl-5-benzyl-2-methyl-4-phenylethynyl-6-phenyl-1,4-(+/-)-dihydropyridine-3,5-dicarboxylate (MRS1191) could restore and further augment responses. The IB-MECA effect was resistant to knockdown of adenosine A1 receptor with the irreversible antagonist FSCPX; the IC(50) for IB-MECA was 0.8 microM. MRS1191 alone could augment or unmask coordinated responses to dimaprit, and IB-MECA suppressed them. MRS1191 augmented distension-evoked reflex I(sc) responses. Adenosine deaminase mimicked actions of adenosine receptor antagonists. A3 receptor immunoreactivity was differentially expressed in enteric neurons of different parts of colon. After tetrodotoxin, IB-MECA caused circular muscle relaxation. The data support the novel concept that eADO acts at low-affinity A3 receptors in addition to high-affinity A1 receptors to suppress coordinated responses triggered by immune-histamine H2 receptor activation. The short interplexus circuit activated by histamine involves adenosine, acetylcholine, substance P, and serotonin. We postulate that A3 receptor modulation may occur in gut inflammatory diseases or allergic responses involving mast cell and histamine release.

Topics: Adenosine; Animals; Chlorides; Cimetidine; Colon; Dihydropyridines; Dimaprit; Dose-Response Relationship, Drug; Enteric Nervous System; Gastrointestinal Motility; Guinea Pigs; Histamine; Histamine Agonists; Histamine H2 Antagonists; In Vitro Techniques; Intestinal Secretions; Male; Mecamylamine; Muscle Contraction; Muscle Relaxation; Muscle, Smooth; Neural Inhibition; Neurogenic Bowel; Neurokinin-1 Receptor Antagonists; Nicotinic Antagonists; Piperidines; Propane; Receptor, Adenosine A1; Receptor, Adenosine A3; Receptors, Histamine H2; Receptors, Neurokinin-1; Reflex; Theophylline; Xanthines