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Bladder

The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

Robert M. Levin – 1st expert on this subject based on the ideXlab platform

  • Bladder outlet obstruction accelerates Bladder carcinogenesis
    BJUI, 2008
    Co-Authors: Seiji Matsumoto, Nobutaka Shimizu, Tadashi Hanai, Hirotsugu Uemura, Robert M. Levin

    Abstract:

    OBJECTIVE

    To examine the correlation between partial Bladder outlet obstruction (PBOO) and Bladder carcinogenesis.

    MATERIALS AND METHODS

    Female Wistar rats (6 weeks old) were divided into three groups of 10 each: group 1 was exposed to n-butyl-n-butanol nitrosamine (BBN, a carcinogen) in drinking water for 8 weeks; group 2 had PBOO induced surgically after exposure to BBN for 8 weeks; group 3 had a sham operation and the rats drank normal water (control group). After 20 weeks, all of the rats were killed humanely and their Bladders analysed.

    RESULTS

    There were no significant differences in body weight among the groups. The Bladder weight of group 2 was significantly greater than either group 1 or group 3. Histopathologically, Bladder smooth muscle hypertrophy was the major cause of the increased Bladder weight for group 2. In group 2 there were increases in Bladder wall thickness and many nipple-shaped urothelial tumours. Basic fibroblast growth factor and hypoxia-inducible factor-1α expression were significantly greater in group 2 than in groups 1 and 3.

    CONCLUSIONS

    Exposure of the Bladder to carcinogens during Bladder hyperplasia and hypertrophy induced by PBOO results in a greater incidence of superficial Bladder carcinoma.

  • Metabolic basis for contractile dysfunction following chronic partial Bladder outlet obstruction in rabbits
    Molecular and Cellular Biochemistry, 1999
    Co-Authors: Denise A. Nigro, Alan J. Wein, Niels Haugaard, Robert M. Levin

    Abstract:

    Prior studies have shown that partial outlet obstruction of the rabbit Bladder causes a progressive increase in Bladder mass, a progressive decrease in the contractile response to different forms of stimulation, and a selective decrease in the activity of mitochondrial enzymes. In this investigation the contractile responses to field stimulation and bethanechol were directly correlated with the activity of citrate synthase as a function of both the duration of obstruction and the Bladder mass. Partial Bladder outlet obstruction was surgically induced in twenty New Zealand White rabbits. The Bladders were then rapidly excised at 30, 40, 90, 105 or 150 days post obstruction. The contractile responses to field stimulation (32 Hz) and bethanechol (250 μM) were determined. The remainder of the Bladders were frozen and used for citrate synthase activity determinations. The data were grouped for analysis both by the duration of obstruction and by the Bladder mass. Chronic partial outlet obstruction caused a parallel decline in the activity of citrate synthase and in the response of the obstructed tissue to stimulation.

  • mitochondrial and mitochondia related nuclear genetic function in rabbit urinary Bladder following reversal of outlet obstruction
    Molecular and Cellular Biochemistry, 1999
    Co-Authors: Christina A Nevelmcgarvey, Robert M. Levin, Dorothea Rohrmann, Alan P Hudson

    Abstract:

    Partial outlet obstruction of the rabbit urinary Bladder causes increased tissue hypertrophy and decreased contractility of that organ; we showed that, in an experimental rabbit model, both correlate closely with alterations in the status and expression of mitochondrial (mt), and mt-related nuclear, genetic parameters in Bladder smooth muscle. Here we investigate the rate and overall level of recovery of mt and nuclear genetic function following reversal of outlet obstruction in the same animal model. Release from outlet obstruction at 28 days resulted in improvement in both level of hypertrophy and contractile function in all Bladders studied. However, Bladders fell into two groups based on whether relative copy mt genome number per cell was above or below that of unobstructed controls. Bladders with high mt DNA content adjusted organellar genome copy number toward normal post-reversal but did not properly adjust mt transcript levels; mt-related nuclear transcripts in these samples showed recovery. Bladders with low mt DNA content showed no adjustment of those levels toward normal post-reversal but did show some adjustment in other mt and nuclear genetic parameters. Thus, a limiting factor for return of normal Bladder function following reversal of outlet obstruction may be recovery of normal mt genetic performance.

Penelope A. Longhurst – 2nd expert on this subject based on the ideXlab platform

  • Modulation of Urinary Bladder Function by Sex Hormones in Streptozotocin-Diabetic Rats
    The Journal of Urology, 1994
    Co-Authors: Berit Eika, Robert M. Levin, Penelope A. Longhurst

    Abstract:

    AbstractThe modulation of urinary Bladder function by sex hormones was examined in castrated and sham-operated male and female streptozotocin-diabetic rats. Male and female diabetic rats weighed less than age-matched controls and had significantly greater serum glucose levels and Bladder weights. Castration had no effect on Bladder mass and did not alter the diabetes-induced changes in rat or Bladder mass. Protein concentrations were significantly increased and collagen concentrations were significantly decreased in Bladders from diabetic rats compared with nondiabetics. Sex or castration had no effects on protein or collagen concentration of Bladders from nondiabetic and diabetic rats. There were no differences in water consumption and urine excretion between male and female nondiabetic rats, and no effects of castration were observed on micturition in nondiabetic rats. Ovariectomy followed by diabetes caused a significant increase in urine excretion compared with diabetes alone. Ovariectomized diabetic …

  • Modulation of urinary Bladder function by sex hormones in streptozotocin-diabetic rats.
    The Journal of urology, 1994
    Co-Authors: Berit Eika, Robert M. Levin, Penelope A. Longhurst

    Abstract:

    The modulation of urinary Bladder function by sex hormones was examined in castrated and sham-operated male and female streptozotocin-diabetic rats. Male and female diabetic rats weighed less than age-matched controls and had significantly greater serum glucose levels and Bladder weights. Castration had no effect on Bladder mass and did not alter the diabetes-induced changes in rat or Bladder mass. Protein concentrations were significantly increased and collagen concentrations were significantly decreased in Bladders from diabetic rats compared with non-diabetics. Sex or castration had no effects on protein or collagen concentration of Bladders from nondiabetic and diabetic rats. There were no differences in water consumption and urine excretion between male and female nondiabetic rats, and no effects of castration were observed on micturition in nondiabetic rats. Ovariectomy followed by diabetes caused a significant increase in urine excretion compared with diabetes alone. Ovariectomized diabetic rats had increased mean and maximal micturition volumes when compared with other female rats. Orchiectomy had no effects on the expected increases in micturition associated with diabetes. Diabetes in male rats caused significant increases in contractile responses of Bladder strips to field stimulation, carbachol, KCl and high concentrations of ATP. In both nondiabetic and diabetic groups, orchiectomy had no effects on the contractile responses compared with sham operation. Similarly, in Bladder strips from diabetic females, contractile responses to carbachol, KCl and high concentrations of ATP were significantly increased compared with those of nondiabetics, and were unchanged by ovariectomy. However, ovariectomy in nondiabetic rats caused significant decreases in contractile responsiveness to nerve stimulation, effects which were only partially prevented by diabetes. The data suggest that there are few differences between male and female rats in their sensitivity to streptozotocin and the effects of diabetes on micturition, Bladder collagen and protein concentration, and the responsiveness of Bladder strips to contractile agents. The changes in Bladder function observed after induction of diabetes do not appear to be related to changes in sex hormone levels. The major differences noted between males and females were the decreased responsiveness of Bladders from nondiabetic ovariectomized female rats to field stimulation. In conjunction with previous data obtained in this laboratory, the study suggests that the responses to field stimulation are more sensitive to the effects of ovariectomy than are the responses to contractile agonists.

  • comparison of urinary Bladder function in rats with hereditary diabetes insipidus streptozotocin induced diabetes mellitus and nondiabetic osmotic diuresis
    The Journal of Urology, 1994
    Co-Authors: Berit Eika, Penelope A. Longhurst, Robert M. Levin

    Abstract:

    Abstract In vivo and in vitro Bladder function were studied in three different models of increased diuresis: 1) Brattleboro rats with hereditary diabetes insipidus (di/di), 2) Sprague-Dawley rats with streptozotocin-induced diabetes mellitus (STZ), and 3) Sprague-Dawley rats with increased diuresis due to 5% sucrose added to the drinking water. When compared with controls, all three models showed Bladder mass, increased water consumption and urine output, higher mean and maximal increased micturition volumes, and greater Bladder capacity and compliance by in vitro cystometry. The changes were more extensive in di/di rats than in STZ and sucrose-drinking rats. The concentration of Bladder collagen decreased in all three rat models when compared with controls. However, the collagen concentration of STZ Bladders was significantly lower than the collagen concentration of di/di and sucrose Bladders, suggesting that the decrease in Bladder collagen concentration associated with experimental diabetes mellitus is only partly related to the increased diuresis. Contractile function was studied using a whole Bladder model. Responses of whole Bladders from control and diabetic rats to electrical field stimulation, carbachol and KCl were identical. Volume-pressure relations of the isolated whole Bladder showed that the magnitude of the contractile response to KCl is constant at intravesical volumes ranging from about 10 to 95% of cystometrical Bladder capacity. Bladders from Brattleboro di/di rats and STZ rats showed a rightward shift of volume-passive pressure curves when compared with appropriate controls. Bladders from sucrose-drinking rats had volume-passive pressure curves similar to the Bladders from controls. This study suggests that while contractile function remains intact with increased diuresis, the passive function changes, with the Bladder becoming more distensible.

Berit Eika – 3rd expert on this subject based on the ideXlab platform

  • Modulation of Urinary Bladder Function by Sex Hormones in Streptozotocin-Diabetic Rats
    The Journal of Urology, 1994
    Co-Authors: Berit Eika, Robert M. Levin, Penelope A. Longhurst

    Abstract:

    AbstractThe modulation of urinary Bladder function by sex hormones was examined in castrated and sham-operated male and female streptozotocin-diabetic rats. Male and female diabetic rats weighed less than age-matched controls and had significantly greater serum glucose levels and Bladder weights. Castration had no effect on Bladder mass and did not alter the diabetes-induced changes in rat or Bladder mass. Protein concentrations were significantly increased and collagen concentrations were significantly decreased in Bladders from diabetic rats compared with nondiabetics. Sex or castration had no effects on protein or collagen concentration of Bladders from nondiabetic and diabetic rats. There were no differences in water consumption and urine excretion between male and female nondiabetic rats, and no effects of castration were observed on micturition in nondiabetic rats. Ovariectomy followed by diabetes caused a significant increase in urine excretion compared with diabetes alone. Ovariectomized diabetic …

  • Modulation of urinary Bladder function by sex hormones in streptozotocin-diabetic rats.
    The Journal of urology, 1994
    Co-Authors: Berit Eika, Robert M. Levin, Penelope A. Longhurst

    Abstract:

    The modulation of urinary Bladder function by sex hormones was examined in castrated and sham-operated male and female streptozotocin-diabetic rats. Male and female diabetic rats weighed less than age-matched controls and had significantly greater serum glucose levels and Bladder weights. Castration had no effect on Bladder mass and did not alter the diabetes-induced changes in rat or Bladder mass. Protein concentrations were significantly increased and collagen concentrations were significantly decreased in Bladders from diabetic rats compared with non-diabetics. Sex or castration had no effects on protein or collagen concentration of Bladders from nondiabetic and diabetic rats. There were no differences in water consumption and urine excretion between male and female nondiabetic rats, and no effects of castration were observed on micturition in nondiabetic rats. Ovariectomy followed by diabetes caused a significant increase in urine excretion compared with diabetes alone. Ovariectomized diabetic rats had increased mean and maximal micturition volumes when compared with other female rats. Orchiectomy had no effects on the expected increases in micturition associated with diabetes. Diabetes in male rats caused significant increases in contractile responses of Bladder strips to field stimulation, carbachol, KCl and high concentrations of ATP. In both nondiabetic and diabetic groups, orchiectomy had no effects on the contractile responses compared with sham operation. Similarly, in Bladder strips from diabetic females, contractile responses to carbachol, KCl and high concentrations of ATP were significantly increased compared with those of nondiabetics, and were unchanged by ovariectomy. However, ovariectomy in nondiabetic rats caused significant decreases in contractile responsiveness to nerve stimulation, effects which were only partially prevented by diabetes. The data suggest that there are few differences between male and female rats in their sensitivity to streptozotocin and the effects of diabetes on micturition, Bladder collagen and protein concentration, and the responsiveness of Bladder strips to contractile agents. The changes in Bladder function observed after induction of diabetes do not appear to be related to changes in sex hormone levels. The major differences noted between males and females were the decreased responsiveness of Bladders from nondiabetic ovariectomized female rats to field stimulation. In conjunction with previous data obtained in this laboratory, the study suggests that the responses to field stimulation are more sensitive to the effects of ovariectomy than are the responses to contractile agonists.

  • comparison of urinary Bladder function in rats with hereditary diabetes insipidus streptozotocin induced diabetes mellitus and nondiabetic osmotic diuresis
    The Journal of Urology, 1994
    Co-Authors: Berit Eika, Penelope A. Longhurst, Robert M. Levin

    Abstract:

    Abstract In vivo and in vitro Bladder function were studied in three different models of increased diuresis: 1) Brattleboro rats with hereditary diabetes insipidus (di/di), 2) Sprague-Dawley rats with streptozotocin-induced diabetes mellitus (STZ), and 3) Sprague-Dawley rats with increased diuresis due to 5% sucrose added to the drinking water. When compared with controls, all three models showed Bladder mass, increased water consumption and urine output, higher mean and maximal increased micturition volumes, and greater Bladder capacity and compliance by in vitro cystometry. The changes were more extensive in di/di rats than in STZ and sucrose-drinking rats. The concentration of Bladder collagen decreased in all three rat models when compared with controls. However, the collagen concentration of STZ Bladders was significantly lower than the collagen concentration of di/di and sucrose Bladders, suggesting that the decrease in Bladder collagen concentration associated with experimental diabetes mellitus is only partly related to the increased diuresis. Contractile function was studied using a whole Bladder model. Responses of whole Bladders from control and diabetic rats to electrical field stimulation, carbachol and KCl were identical. Volume-pressure relations of the isolated whole Bladder showed that the magnitude of the contractile response to KCl is constant at intravesical volumes ranging from about 10 to 95% of cystometrical Bladder capacity. Bladders from Brattleboro di/di rats and STZ rats showed a rightward shift of volume-passive pressure curves when compared with appropriate controls. Bladders from sucrose-drinking rats had volume-passive pressure curves similar to the Bladders from controls. This study suggests that while contractile function remains intact with increased diuresis, the passive function changes, with the Bladder becoming more distensible.