Clinical evaluation of long-term indwelling of Allium ureteral stent in the treatment of ureteral stricture / 现代泌尿外科杂志

【Objective】 To evaluate the safety and efficacy of long-term indwelling of Allium ureteral stent in the treatment of ureteral stricture. 【Methods】 The clinical data of patients who underwent endoscopic Allium ureteral stent implantation for ureteral stricture in our hospital during Aug.2020 and Dec.2022 were retrospectively analyzed, and the surgical conditions and adverse events were recorded. The data of serum creatinine, blood urea nitrogen, glomerular filtration rate (GFR) and renal pelvis width under ultrasound were compared before surgery and 1, 3, 6 and 12 months after surgery. 【Results】 A total of 52 patients with ureteral stricture of 1.1 (0.7, 2.0)cm were included. All operations were successful. The operation time was 82.5 (70, 114)min, intraoperative blood loss 20 (10, 20)mL, and postoperative hospitalization stay 1 (1, 2) day. During the follow-up of (13.2±7.8) months, 14 patients had stent displacement, 5 had stone obstruction of stent tubes, 7 had occasional hematuria after movement, 9 had intermittent lumbar and abdominal pain, and 1 had recurrent urinary tract infection. The serum creatinine, blood urea nitrogen and renal pelvis width of 1 month, 3, 6 and 12 months after surgery were significantly decreased, while GFR was significantly increased. 【Conclusion】 Long-term indwelling of Allium ureteral stent is effective in the treatment of ureteral stricture, but the high incidence of stent displacement should arouse attention.

Cyclophosphamide-induced HCN1 channel upregulation in interstitial Cajal-like cells leads to bladder hyperactivity in mice

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are confirmed to be expressed in bladder interstitial Cajal-like cells (ICC-LCs), but little is known about their possible role in cystitis-associated bladder dysfunction. The present study aimed to determine the functional role of HCN channels in regulating bladder function under inflammatory conditions. Sixty female wild-type C57BL/6J mice and sixty female HCN1-knockout mice were randomly assigned to experimental and control groups, respectively. Cyclophosphamide (CYP)-induced cystitis models were successfully established in these mice. CYP treatment significantly enhanced HCN channel protein expression and I(h) density and significantly altered bladder HCN1 channel regulatory proteins. Carbachol (CCH) and forskolin (FSK) exerted significant effects on bladder ICC-LC [Ca²⁺]i in CYP-treated wild-type (WT) mice, and HCN1 channel ablation significantly decreased the effects of CCH and FSK on bladder ICC-LC [Ca²⁺]i in both naive and CYP-treated mice. CYP treatment significantly potentiated the spontaneous contractions and CCH (0.001-10 µM)-induced phasic contractions of detrusor strips, and HCN1 channel deletion significantly abated such effects. Finally, we demonstrated that the development of CYP-induced bladder overactivity was reversed in HCN1 -/- mice. Taken together, our results suggest that CYP-induced enhancements of HCN1 channel expression and function in bladder ICC-LCs are essential for cystitis-associated bladder hyperactivity development, indicating that the HCN1 channel may be a novel therapeutic target for managing bladder hyperactivity.

Role of hyperpolarization-activated cyclic nucleotide-gated cation nonselective channel in spontaneous contrac-tion of smooth muscles in human isolated ureters / 局解手术学杂志

Objective To investigate effects of hyperpolarization-activated cyclic nucleotide-gated cation nonselective channel in the hu-man ureter on the spontaneous contraction of smooth muscles. Methods Four HCN subtypes were detected in human ureteral tissue using reverse transcription polymerase chain reaction,Western blotting and immunohistochemical. ZD7288,the HCN blocker, was used to observe the changes of ureteral muscle contraction amplitude and frequency by applying the ureteral smooth muscle strip test in vitro. Results HCN1-4 isoforms were all identified in human ureter using reverse transcription-polymerase chain reaction and Western blotting. Through the immunohistochemical,HCN channel was found mostly in the urothelium layer and muscular layer of human ureteral wall. ZD7288 significantly decreased the bladder excitation. Conclusion All 4 HCN channel hypotypes exist in the human ureter, and affect the ureteral excitation.