Reversibility of diabetes- and diuresis-induced alterations in rat bladder dome muscarinic receptors

Effects of insulin treatment on diabetes‐induced alterations in endothelin receptors in rat ureter

“…1, Table 2). Densities of ET receptors in the D 8 and D 16 ureters calculated on the basis of protein or tissue concentrations were significantly higher than that of their age matched control ureters. Both 8 and 16 weeks of experimental diabetes caused a similar up-regulation in the density of ET receptors in ureters indicating that a further increase in the duration of diabetes beyond 8 weeks did not increase the magnitude of the ET receptor upregulation.…”

“…Although DI 16 animals were significantly heavier than D 16 animals (138% of D 16 animals), the ureteral weights of the DI 16 group were only slightly, but not significantly, lower than that of the D 16 group. Furthermore, the D 8 and D 16 animals had significantly greater serum glucose levels and lower serum insulin levels than the other groups. Diabetes induced polydipsia and polyuria were improved by the insulin treatment (data not shown).…”

“…At the time of sacrifice, bodyweights in the D 8 and D 16 groups were significantly lower than the age-matched control groups (45 and 52% of control animals, respectively) and ureteral weights of the D 8 and D 16 groups were significantly greater than those of the C 8 and C 16 groups (165 and 146% of respective control groups, respectively). Although DI 16 animals were significantly heavier than D 16 animals (138% of D 16 animals), the ureteral weights of the DI 16 group were only slightly, but not significantly, lower than that of the D 16 group. Furthermore, the D 8 and D 16 animals had significantly greater serum glucose levels and lower serum insulin levels than the other groups.…”

“…To characterize ET receptor subtypes in control, diabetic and diabetic-insulin treated ureters, inhibition experiments were carried out with calculation of inhibition constants (K i values) for various compounds in ureteral membranes of D 16 , DI 16 and C 16 and in cloned human ET A and ET B receptors in CHO cells. 20 In inhibition binding studies, the ureteral membrane suspensions were diluted in the incubation buffer to approximately 400 volumes and stock mem-brane preparations of cloned human ET A or ET B receptors were diluted to 4-6 fmol/mL with the incubation buffer.…”

“…adrenergic and cholinergic receptors) may be involved in the development of diabetes-induced pathologic conditions involving urinary bladder smooth muscle. [14][15][16] Clinically, diabetic patients have a higher incidence of pyelonephritis and hydronephrosis, which may be due to dysfunction of the ureter. 17 As recent reports indicate that ET and ET receptors characteristics in the cardiovascular system are altered by insulin-dependent diabetes, 18,19 we investigated the effects of experimentally induced diabetes and the insulin treatment of the diabetes on the properties of ET receptors in the rat ureter.…”