Biochemical characterization of the rabbit urinary bladder: II. Intracellular concentration of nucleotides

Abstract

Bladder contraction is mediated by a number of intracellular biochemical reactions including glycolysis, mitochondria1 respiration, phosphocreatine kinase, and various ATPases. In order to understand how alterations in intracellular metabolism can affect bladder function (or how alterations in bladder function can affect intracellular metabolism), we must first understand and describe normal bladder metabolism. Using the rabbit as a model for bladder function, the present study compares the intracellular concentrations of a variety of important compounds between the bladder base and body.The intracellular concentrations of phosphocreatine (PC), creatine, ATP, ADP, and AMP were determined in samples of rabbit urinary bladder body and base. The values for PC and creatine were significantly lower in the bladder base than in the bladder body. Adenine nucleotide concentrations were similar in the two sections.The concentrations of NAD + NADH, NADP, CTP, CDP, CMP, GTP, GDP, GMP, and UTP, UDP, UMP were also measured. Of these compounds, the concentrations of GTP and UTP in the bladder body were nearly double those in the bladder base. The intracellular concentrations of the other tissue constituents were similar in the two bladder sections.These studies demonstrate that the bladder is not biochemically homogeneous but that the bladder base and body differ not only functionally but also metabolically.Experiments in which strips of bladder body were incubated in vitro in oxygenated Tyrode's solution containing glucose showed that the tissue concentrations of PC, ATP, GTP, and UTP decreased substantially following 30 min of incubation, with no further decrease during a subsequent 60-min incubation.

Effects of partial outlet obstruction on bladder-strip sensitivity to glucose deprivation: an in vitro study in the rat

“…Although it is generally accepted that smooth-muscle function is dependent on the metabolism of substrates, there is little detailed information on the relationship between substrate utilization and contractile function [4,5,8,11,14,17,18]. The current studies demonstrate that the phasic responses to stimuli were relatively well maintained in the presence of glucose in both control and obstructed strips.…”

Effect of partial outlet obstruction on14C-adenine incorporation in the rabbit urinary bladder

“…Urinary bladder contraction utilizes ATP derived from both glycolytic (anaerobic) and oxidative metabolism Lin et al, 1992;Polyanska et al, 1993;Scott and Coburn, 1989;Hellstrand and Vogel, 1985;Levin et al, 1987a;Levin et al, 1989]. Bladder contraction is biphasic; there is a rapid rise in tension to a maximum (peak force) followed by a prolonged period of sustained tension (tonic Fig.…”

“…phosphates Lin et al, 1992;Polyanska et al, 1993;Scott and Coburn, 1989;Hellstrand and Vogel, 1985;Levin et al, 1989;Levin et al, 1987a]. In general, the contractile response of the bladder can be divided into 2 phases: an initial increase in force (peak phase) followed in time by a prolonged period of increased force (plateau phase) [Levin et al, 1987b;Bilgen et al, 1992].…”