A study on the viscoelastic properties of the urinary bladder in dogs.

This experimental study was designed and carried out in order to investigate the participation of the collagen and muscular tissues on the viscoelastic properties of the bladder wall. Sixty-five adult male mongrel dogs were utilized. These animals were divided into 5 groups: control group (n = 10); dogs (n = 10) receiving 2.5 mg/kg atropine (cholinergic antagonist); dogs (n = 10) receiving 0.7 mg/kg verapamil (calcium extracellular inflow blocker); dogs (n = 10) receiving 0.1 mg/kg/min nitroprusside (intracellular calcium blocker), and dogs (n = 25) receiving EGTA (a calcium-chelating agent) at increasing doses from 90 to 450 mg/kg. Based on a mathematical model, we have demonstrated that: (1) the collagen component is responsible for the elastic properties; (2) the muscle component is responsible for the viscoelastic properties; (3) the viscoelastic properties have an active element which is affected by calcium total depletion, and (4) such viscoelastic properties are not dependent on cholinergic stimulation.

Importance of the active component of the detrusor muscle in bladder compliance.

An appropriate experimental study was designed and carried out in mongrel dogs, in order to evaluate the active muscle and cholinergic participation on bladder compliance. The filling bladder pressure was measured at 100 ml of bladder volume, in 50 dogs distributed into five groups of 10 dogs each: (1) control group, (2) group which received atropine (cholinergic antagonist), (3) group which received verapamil (extracellular Ca2+ blocker), (4) group which received nitroprusside (intracellular Ca2+ antagonist), and (5) group which received EGTA (Ca(2+)-chelating agent). Furthermore, the following was demonstrated. (1) The greatest decrease of the bladder filling pressure was observed in the group which was treated with EGTA. (2) A significant decrease of the bladder filling pressure was also seen in the group which was given nitroprusside. (3) The decrease of bladder filling pressure in the verapamil group tended towards statistical significance. (4) There was no decrease in the atropine group. Thus, it was concluded that the active muscle component has an important role in the bladder compliance (through the intracellular calcium fraction), and the cholinergic component does not participate in the bladder compliance.

Genuine hereditary hydronephrosis in a three-generation family. Clinicopathological and genetic implications with a review of the literature.

The clinical features and management of genuine hereditary hydronephrosis (GHH) in 4 members of the same family are presented. Genealogical studies provide evidence of a dominant autosomal inheritance with complete penetrance. All affected members of the family had inherited the same HLA haplotype through the male line. This finding, added to those from previous association studies with histocompatibility typing (in 3 families), lends support to the localization of the GHH gene/s in the 6p human chromosome. Based on our findings from the present familial study and on a review of the literature, we suggest that all first-degree relatives of children or adults with genuine hydronephrosis should be screened by ultrasound. Such a prospective screening, including fetal echography, will lead to earlier diagnosis and treatment of asymptomatic cases and, moreover, will identify GHH cases for possible genetic counseling with regard to the empiric recurrence risk.

The natural history and course of untreated benign prostatic hyperplasia.

An understanding of the natural history or developmental growth and clinicopathologic evolution of benign prostatic hyperplasia (BPH) is important in assessing prognosis, providing adequate treatment, and evaluating the potential usefulness of newer therapeutic agents. Currently, the general view is that BPH is basically a progressive disease characterized by different growth rates in different individuals. However, the reason for possible fluctuations in growth rate, or even that of spontaneous regression in some individuals as the result of unknown endogenous factors in the host, remains to be determined.

Hepatic acetylator phenotype in bladder cancer patients.

We determined the hepatic acetylator phenotype in 130 patients with transitional-cell carcinoma (urothelioma) of the bladder and, previously in 157 normal control subjects. Eighty-three patients (63.8%) and 90 control subjects (57.4%) were slow acetylators (p greater than 0.05). Patients of both phenotypes did not differ in the consumption of tobacco and coffee. Seventy-five patients were not exposed to occupational risk for bladder cancer and the distribution of acetylator phenotype in them was similar to that of the control group. The other 55 patients had been employed in jobs with an elevated risk for urotheliomas; 41 (74.5%) were slow acetylators, which represented a significant excess over the incidence of slow acetylators in the control group (57.4%) (p less than 0.05); 15 of these patients had worked in jobs with carcinogenic arylamines proven in the workplace environment (11 were slow acetylators). Our results suggest that the slow acetylator phenotype can facilitate the development of urothelioma in individuals with occupational risk.

A spectrum of malignant epithelial tumors of the prostate gland.

Conceptually, the prostatic territory encompasses neoplams whose origins are intraprostatic, paraprostatic or extraprostatic. Our objectives in this review are to 1) present a classification of the spectrum of malignant epithelial growth encountered in the prostatic territory, 2) show examples of these neoplasms and remark upon their histogenesis, enzyme production and endocrine sensitivity, and 3) suggest re-evaluation of some of our current routine therapeutic procedures.