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Hardy CC, Al-Naggar IM, Kuo CL, Kuchel GA, Smith PP. Aging Changes in Bladder Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels Are Associated With Increasing Heterogeneity of Adrenergic/Mucosal Influence on Detrusor Control in the Mouse. J Gerontol A Biol Sci Med Sci 2021; 76:1153-1160. [PMID: 33693872 DOI: 10.1093/gerona/glab070] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Indexed: 11/14/2022] Open
Abstract
A geroscience-informed approach to the increasing prevalence of bladder control problems in older adults requires understanding the impact of aging on dynamic mechanisms that ensure resilience in response to stressors challenging asymptomatic voluntary control over urine storage and voiding. Bladder control is predicated on sensory neural information about bladder volume. Modulation of volume-induced bladder wall tensions by autonomic and mucosal factors controls neural sensitivity to bladder volume. We hypothesized that hyperpolarization-activated cyclic nucleotide-gated (HCN) channels integrate these factors and thereby mediate adrenergic detrusor tension control. Furthermore, loss of HCN expression compromises that integration and could result in loss of precision of detrusor control. Using a life-span mouse model, reverse transcription quantitative real-time PCR and pharmacologic studies in pretensioned intact and mucosa-denuded bladder strips were made. The dominant hcn1 expression declines with maturation and aging; however, aging is also associated with increased variance around mean values. In strips from Mature animals, isoproterenol had less effect in denuded muscle strips than in intact strips, and HCN blockade diminished isoproterenol responsiveness. With aging, variances about mean response values significantly increased, paralleling hcn1 expression. Our findings support a role for HCN in providing neuroendocrine/paracrine integration and suggest an association of increased heterogeneity of HCN expression in aging with reductions in response precision to neuroendocrine control. The functional implication is an increased risk of dysfunction of brainstem/bladder regulation of neuronal sensitivity to bladder volume. This supports the clinical model of the aging bladder phenotype as an expression of loss of resilience, and not as emerging bladder pathology with aging.
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Affiliation(s)
- Cara C Hardy
- Center on Aging, University of Connecticut School of Medicine, Farmington, USA.,Department of Neuroscience, University of Connecticut School of Medicine, Farmington, USA.,Connecticut Institute for the Brain and Cognitive Sciences, University of Connecticut, Storrs, USA
| | - Iman M Al-Naggar
- Center on Aging, University of Connecticut School of Medicine, Farmington, USA
| | - Chia-Ling Kuo
- Center on Aging, University of Connecticut School of Medicine, Farmington, USA.,Connecticut Convergence Institute for Translation in Regenerative Engineering, UConn Health, Farmington, USA
| | - George A Kuchel
- Center on Aging, University of Connecticut School of Medicine, Farmington, USA.,Department of Neuroscience, University of Connecticut School of Medicine, Farmington, USA.,Connecticut Institute for the Brain and Cognitive Sciences, University of Connecticut, Storrs, USA
| | - Phillip P Smith
- Center on Aging, University of Connecticut School of Medicine, Farmington, USA.,Department of Neuroscience, University of Connecticut School of Medicine, Farmington, USA.,Connecticut Institute for the Brain and Cognitive Sciences, University of Connecticut, Storrs, USA.,Department of Surgery, University of Connecticut School of Medicine, Farmington, USA
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Ji Q, Zhang Y, Zhang H, Liu J, Cao C, Yuan Z, Ma Q, Zhang W. Effects of β-adrenoceptor activation on haemodynamics during hypoxic stress in rats. Exp Physiol 2020; 105:1660-1668. [PMID: 32706493 DOI: 10.1113/ep088669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 07/23/2020] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? The acute hypoxic compensatory reaction is based on haemodynamic changes, and β-adrenoceptors are involved in haemodynamic regulation. What is the role of β-adrenoceptors in haemodynamics during hypoxic exposure? What is the main finding and its importance? Activation of β2 -adrenoceptors attenuates the increase in pulmonary artery pressure during hypoxic exposure. This compensatory reaction activated by β2 -adrenoceptors during hypoxic stress is very important to maintain the activities of normal life. ABSTRACT The acute hypoxic compensatory reaction is accompanied by haemodynamic changes. We monitored the haemodynamic changes in rats undergoing acute hypoxic stress and applied antagonists of β-adrenoceptor (β-ARs) subtypes to reveal the regulatory role of β-ARs on haemodynamics. Sprague-Dawley rats were randomly divided into control, atenolol (β1 -AR antagonist), ICI 118,551 (β2 -AR antagonist) and propranolol (non-selective β-AR antagonist) groups. Rats were continuously recorded for changes in haemodynamic indexes for 10 min after administration. Then, a hypoxic ventilation experiment [15% O2 , 2200 m a.sl., 582 mmHg (0.765 Pa), P O 2 87.3 mmHg; Xining, China] was conducted, and the indexes were monitored for 5 min after induction of hypoxia. Plasma catecholamine concentrations were also measured. We found that, during normoxia, the mean arterial pressure, heart rate, ascending aortic blood flow and pulmonary artery pressure were reduced in the propranolol and atenolol groups. Catecholamine concentrations were increased significantly in the atenolol group compared with the control group. During hypoxia, mean arterial pressure and total peripheral resistance were decreased in the control, propranolol and ICI 118,551 groups. Pulmonary arterial pressure and pulmonary vascular resistance were increased in the propranolol and ICI 118,551 groups. During hypoxia, catecholamine concentrations were increased significantly in the control group, but decreased in β-AR antagonist groups. In conclusion, the β2 -AR is involved in regulation of pulmonary haemodynamics in the acute hypoxic compensatory reaction, and the activation of β2 -ARs attenuates the increase in pulmonary arterial pressure during hypoxic stress. This compensatory reaction activated by β2 -ARs during hypoxic stress is very important to maintain activities of normal life.
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Affiliation(s)
- Qiaorong Ji
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Yu Zhang
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Huan Zhang
- Department of Pathology, Weinan Central Hospital, Shengli street, Weinan, Shaanxi, 714000, China
| | - Jie Liu
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Chengzhu Cao
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Zhouyang Yuan
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Qianqian Ma
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
| | - Wei Zhang
- Department of Basic Medicine, Medical College of Qinghai University, No.16 kunlun road, Xining, Qinghai, 810001, China.,Pathophysiology Laboratory, The Key Laboratory of Science and Technology for High Altitude Medicine, No.16 kunlun road, Xining, Qinghai, 810001, China
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Propping S, Lorenz K, Michel MC, Wirth MP, Ravens U. β-Adrenoceptor-mediated Relaxation of Urinary Bladder Muscle in β2-Adrenoceptor Knockout Mice. Front Pharmacol 2016; 7:118. [PMID: 27242525 PMCID: PMC4860462 DOI: 10.3389/fphar.2016.00118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 04/22/2016] [Indexed: 11/13/2022] Open
Abstract
Background and Objective: In order to characterize the β-adrenoceptor (AR) subtypes involved in agonist-stimulated relaxation of murine urinary bladder we studied the effects of (-)-isoprenaline and CL 316,243 on tonic contraction and spontaneous contractions in detrusor strips of wild-type (WT) and β2-AR knockout (β2-AR KO) mice. Materials and Methods: Urinary bladders were isolated from male WT and β2-AR KO mice. β-AR subtype expression was determined with quantitative real-time PCR. Intact muscle strips pre-contracted with KCl (40 mM) were exposed to cumulatively increasing concentrations of (-)-isoprenaline or β3-AR agonist CL 316,243 in the presence and absence of the subtype-selective β-AR blockers CGP 20712A (β1-ARs), ICI 118,551 (β2-ARs), and L748,337 (β3-ARs). Results: Quantitative real-time PCR confirmed lack of β2-AR expression in bladder tissue from β2-AR KO mice. In isolated detrusor strips, pre-contraction with KCl increased basal tone and enhanced spontaneous activity significantly more in β2-AR KO than in WT. (-)-Isoprenaline relaxed tonic tension and attenuated spontaneous activity with similar potency, but the concentrations required were two orders of magnitude higher in β2-AR KO than WT. The concentration-response curves (CRCs) for relaxation were not affected by CGP 20712A (300 nM), but were shifted to the right by ICI 118,551 (50 nM) and L748,337 (10 μM). The -logEC50 values for (-)-isoprenaline in WT and β2-AR KO tissue were 7.98 and 6.00, respectively, suggesting a large receptor reserve of β2-AR. (-)-CL 316,243 relaxed detrusor and attenuated spontaneous contractions from WT and β2-AR KO mice with a potency corresponding to the drug’s affinity for β3-AR. L743,337 shifted the CRCs to the right. Conclusion: Our findings in β2-AR KO mice suggest that there is a large receptor reserve for β2-AR in WT mice so that this β-AR subtype will mediate relaxation of tone and attenuation of spontaneous activity under physiological conditions. Nevertheless, upon removal of this reserve, β3-AR can also mediate murine detrusor relaxation.
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Affiliation(s)
- Stefan Propping
- Department of Urology, Faculty of Medicine Carl Gustav Carus, Dresden University of TechnologyDresden, Germany; Department of Physiology, Faculty of Medicine Carl Gustav Carus, Dresden University of TechnologyDresden, Germany
| | - Kristina Lorenz
- Department of Pharmacology and Toxicology, Julius Maximilian University WürzburgWürzburg, Germany; Leibniz-Institute für Analytische Wissenschaften-ISAS-e.V.Dortmund, Germany; West German Heart and Vascular Center Essen, University Hospital Essen-DuisburgDuisburg, Germany
| | - Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University Mainz, Germany
| | - Manfred P Wirth
- Department of Urology, Faculty of Medicine Carl Gustav Carus, Dresden University of Technology Dresden, Germany
| | - Ursula Ravens
- Department of Physiology, Faculty of Medicine Carl Gustav Carus, Dresden University of Technology Dresden, Germany
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