Response of the newborn ureteropelvic junction complex to induced and later reversed partial ureteral obstruction in the rabbit model

The clinical controversy regarding the timing of surgery for asymptomatic newborns with obstructed hydronephrosis was addressed using a model of reversible partial ureteral obstruction in the newborn rabbit. The histomorphometric changes in the ureteropelvic junction complex (for example, pelvis, ureteropelvic junction and upper ureter) and kidney in 44 normal cases were determined and compared with the effects of 47 cases of ongoing partial obstruction and timed reversal of partial obstruction at 1 week in 9 cases, at 2 weeks in 10 or at 4 weeks in 10 (end of the study at age 8 weeks). After partial obstruction hydronephrosis appeared by 1 week postoperatively. There were progressive increases in the thickness of the lamina muscularis and mass index of smooth muscle and collagen (all p < 0.001). However, since the per cent surface area of smooth muscle did not change significantly in comparison to normal, there was disproportionately more collagen. For reversals at 1 week the muscle and collagen in the lamina muscularis were not significantly different from normal. For reversals at 2 weeks the mass index of collagen was greater than normal (p < 0.05) and reversal at 1 week (p < 0.05). For reversals at 4 weeks the lamina muscularis was thicker, and the mass index of collagen and muscle was greater than the earlier reversal groups and normal (all p < 0.05). In conclusion, partial ureteral obstruction causes progressive thickening of the lamina muscularis by collagen and muscle with a disproportionately greater increase in collagen than muscle. The earlier the obstruction can be reversed, the more normal is the ureteropelvic junction complex histology. The functional significance of these changes needs to be determined.

Binding and functional properties of alpha1 adrenoceptors in different regions of the human prostate

The objective of the present study was to determine the density and functional properties of alpha 1 adrenoceptors in different regions of the human prostate. Binding and functional studies were performed on eight different topographical regions of the prostate. The contractile response (gm. force/mm.2 cross-sectional area [CSA]) was determined at varying concentrations of phenylephrine, and saturation experiments were performed at seven different concentrations of 125I-Heat. The maximal response to phenylephrine (Emax) ranged from 0.067 to 0.272 gm. force/mm.2 The CSA and the EC50 ranged from 25 to 41 microM. The differences between EC50 and Emax were not significantly different among the eight prostatic regions. A 1.8-fold difference between the Emax for peripheral and central regions of the prostate was statistically significant (p = 0.04). The equilibrium dissociation constant (Kd) of 125I-Heat and the receptor density Bmax were determined from the Scatchard plots. The mean Kd and Bmax ranged from 0.15 to 0.26 nM. and 0.30 to 0.72 fmol. per mg. wet weight, respectively. There were no statistically significant differences between mean Kd and mean Bmax for the eight prostatic regions. The 1.7-fold difference between central and peripheral mean Bmax was not statistically significant (p = 0.07). A direct relationship was not observed between phenylephrine mean Emax and mean Bmax. The present study demonstrates regional differences of the binding and functional properties of prostatic alpha 1 adrenoceptors in the human prostate. These regional differences must be taken into account when investigating the pharmacologic and physiologic properties of the prostate.

Manitoba's single-entry system to long-term care

A single-entry system does not solve all the problems related to continuity of care, but it gives physicians the opportunity to refer those who may be at risk of losing their capacity to remain in the community to professionals who are qualified to assess the situation, to have their patients who need help access the most appropriate resources, and to have the cooperation of the continuing care workers in providing high-quality care to their patients.

The vulnerable elderly. Predicting necessary resources

This article describes elderly patients who are at risk and the resources they need. It goes on to describe an efficient system that makes optimum use of resources, provides a continuum of care, and makes it easier to predict the resources that a community will require.

Alpha 1 adrenoceptor subtypes in the human prostate

High affinity alpha 1 adrenoceptors have been characterized in the human prostate. The tension of prostatic smooth muscle is mediated by the alpha 1 adrenoceptor. The present study represents the first characterization of human alpha 1 adrenoceptor subtypes using radioligand receptor binding techniques. Binding studies were performed on tissue homogenates obtained from the human prostate. Competitive inhibition studies were performed in the presence of an 80 pM. 125I-Heat and 16 concentrations of unlabelled 5-methylurapidil (5 MU) or WB-4101 (10(-10) M. to 10(-5) M.). Saturation experiments were also performed with and without chloroethylclonidine (CEC, 10(-5) M.), a compound that selectively inactivates the alpha 1B subtype. The individual displacement plots for WB-4101 and 5-MU in the human prostate were consistently best fit by a 2 binding site model. WB-4101 and 5-MU exhibited a 594- and 186-fold higher affinity for the prostatic alpha 1A binding site relative to the alpha 1B binding site. The ratios of prostatic alpha 1A/alpha 1B binding sites discriminated by WB-4101 and 5-MU were 1.8 and 1.6, respectively. CEC inactivated 44% of the prostatic alpha 1 binding sites. The binding studies suggest that the dominant alpha 1 subtype in the human prostate is the alpha 1A. We are characterizing the functional properties of the alpha 1 subtypes in the human prostate.

Evaluation of regional load in acute ischemia by three-dimensional curvatures analysis of the left ventricle

Geometric remodeling of the left ventricule (LV) following myocardial infarction and ischemic insult is associated with myocardial load redistribution. Regional curvatures based on 3-D reconstructions of the LV are used to calculate the regional loads. The technique uses surface normals to derive local circumferential and meridional curvatures. Following the validation of the procedure on simple geometric shapes, the effect of acute ischemia on the regional load redistribution was studied in six open chest dogs. Short axis magnetic resonance imaging (MRI) scans were used to reconstruct end-diastolic (ED) and end-systolic (ES) LV images by applying our helical shape descriptor, before and after acute coronary occlusion. Regional curvatures as well as local wall thickness by the volume element method were calculated before and after acute ischemia, and were used to approximate regional loads, by a regional stress index (sigma/P). Postmortem evaluation using monastral blue staining was used to divide each LV to normal (NZ), ischemic (IZ), and border (BZ) zones in the ischemic case, and to the anatomically matched regions in the preischemic LVs. Ischemia affects the local curvatures and loads both at ED and ES. At ED, sigma/P rose significantly only in the IZ. Similarly, at ES, the highest increase in load was detected in the IZ, but increases in circumferential and meridional load were seen in all regions. Identifying the load redistribution following acute ischemia helps delineate the mechanisms affecting geometric LV remodeling following myocardial infarction.

The alpha-adrenoceptor subtype mediating the tension of human prostatic smooth muscle

We have characterized the alpha 1 adrenoceptor subtypes in the human prostate using radioligand receptor binding studies. The objective of the present study was to determine the alpha 1 subtype mediating the tension of prostatic smooth muscle. Fresh human tissue was obtained from 9 males between 50 and 80 years of age undergoing prostatectomy for BPH. The incubation of prostatic tissue with the irreversible antagonist chlorethyclonidine (CEC) resulted in an 80% reduction of the maximal contractile response produced by phenylephrine. However, the alpha 1A-selective antagonists WB-4101 and 5-methylurapidil (5-MU) competitively inhibited the contractile response induced by phenylephrine, with KB = 2.64 and 4.46 nM, respectively, consistent with their affinity at the alpha 1A receptor subtype. The pharmacological profile of the alpha 1-receptor-mediated contractile response of prostate smooth muscle is inconsistent with their classification as either an alpha 1A or alpha 1B subtype. Alternatively, when compared with the properties of the cloned alpha 1 receptors, our results suggest that the alpha 1 receptors involved in the contraction of prostate smooth muscle have some pharmacological properties similar to those encoded by the gene of the bovine alpha 1C receptor subtype. The findings of the present study suggest that efforts should be made to confirm the identity of the alpha 1-receptor subtype expressed by prostate smooth muscle, in order to develop subtype-selective alpha 1 antagonists, and to evaluate their safety and efficacy in benign prostatic hyperplasia (BPH).

Evaluation of treatment with single-dose ampicillin/sulbactam with probenecid or ceftriaxone in patients with uncomplicated gonorrhea

This study compared ampicillin/sulbactam plus probenecid with ceftriaxone for treatment of uncomplicated gonorrhea. Of the 297 men and women who were enrolled and randomized to receive either ampicillin/sulbactam (1.0 g/0.5 g) with probenecid (1 g) or ceftriaxone (0.25 g), 274 patients were evaluable. Both ampicillin/sulbactam and ceftriaxone were administered by intramuscular injections. Patients were gonococcal contacts, had positive culture results for Neisseria gonorrhoeae, or had clinical evidence of gonorrhea. Specimens for gonococcal cultures were collected from the cervix (female patients), urethra, rectum, and pharynx at pretreatment and test-of-cure visits. The presence of N. gonorrhoeae and a test-of-cure visit were required for drug efficacy analysis. Of the 274 evaluable patients, 195 (71.2%) had positive culture results for N. gonorrhoeae. Cure was achieved in 93 (94.9%) of 98 patients receiving ampicillin/sulbactam with probenecid and in 96 (99.0%) of 97 patients receiving ceftriaxone. Penicillinase-producing N. gonorrhoeae strains were found in 21 (10.8%) patients; these were eradicated by either ampicillin/sulbactam with probenecid (N = 9) or ceftriaxone (N = 12). Overall, the two drug regimens were very well tolerated and no serious adverse effects were noted. Ampicillin/sulbactam with probenecid may be useful as single-dose therapy in patients with uncomplicated genitorectal gonorrhea.

Binding and functional properties of alpha 1 adrenoceptors and area density of smooth muscle in the canine prostate

The present study was designed to compare the area density of smooth muscle, and the binding and functional properties of alpha 1 adrenoceptors in 8 different regions of the canine prostate. The area density of smooth muscle, alpha 1 adrenoceptor density, and contractile response to phenylephrine were investigated using immunoenzymatic staining with color assisted computer image analysis, radioligand receptor binding, and isometric tension studies, respectively. The equilibrium dissociation constants (Kd) for 125I-Heat binding and the alpha 1 adrenoceptor densities (Bmax) in the prostatic regions ranged between 138-230 pM and 0.32-0.52 fmol/wet wt., respectively. The maximal tension generated in the presence of phenylephrine (phenylephrine Emax) and phenylephrine EC50s ranged between 0.043-0.129 gm. force/mm.2 CSA and 4.0-11.0 microM, respectively. The differences between Kd, Bmax, Emax, and EC50 were not significantly different between the different regions of the prostate. The percent area density of smooth muscle ranged between 10.6-24.4%. A direct relationship was not observed between alpha 1 adrenoceptor density and phenylephrine Emax, or alpha 1 adrenoceptor density and percent area density of smooth muscle. A direct relationship was observed between the phenylephrine Emax and percent area density of smooth muscle (p = 0.003; r = 0.90). The phenylephrine Emax and percent area density of smooth muscle was threefold and 1.6-fold greater in the peripheral prostate relative to the central prostate, respectively. The morphometrical and isometric tension studies provides evidence that the canine prostate is a heterogeneous gland.

Clinical versus instrumented knee testing on autopsy specimens

The accuracy, reliability, and reproducibility of the Genucom Knee Analysis System and Knee Signature System (KSS) for anteroposterior knee laxity evaluations were compared. The devices detected the same relative change in laxity between normal and anterior cruciate ligament-deficient specimens during Lachman and drawer testing; however, the absolute values differed. In a clinical study, two examiners performed three independent Lachman and drawer tests using the Genucom, KSS, and a subjective clinical examination on ten patients. The Genucom demonstrated interexaminer differences during the Lachman test. The clinical examination proved to be more reliable than either instrumented device for both Lachman and drawer testing. The intraexaminer variability of the Genucom and KSS was large, with the average 95% confidence limits about the mean for the Genucom and KSS equal to +/- 4.2 and +/- 2.8 mm, respectively. These findings question the accuracy, reliability, and reproducibility of the instrumented methods.

The effect of obstruction on the developing bladder

Congenital bladder obstruction causes significant immediate and long-term consequences yet its pathophysiology remains poorly understood. A model of early fetal bladder obstruction in sheep has been developed to study the response of the developing bladder to high grade obstruction, with particular emphasis on the regulation of growth and development. Congenital bladder obstruction was produced in fetal sheep at 60 days of gestation and studied at 95 days of gestation (14 sheep) or term (12 sheep). A total of 24 age-matched normal sheep served as controls. Bladders were analyzed by total weight, stereological estimation of smooth muscle cell size, number and total mass, deoxyribonucleic acid concentration, muscarinic cholinergic receptor density, myosin isoform analysis and/or passive cystometrics. Congenital bladder obstruction caused a 4.6 times increase in bladder weight at term reflecting a 5.8 times increase in smooth muscle mass. This increase was predominantly that of cellular hypertrophy and less so of hyperplasia, based upon increased cell volume, increased protein-to-deoxyribonucleic acid ratio, and no significant increase in total cell number. Muscarinic cholinergic receptor number per smooth muscle cell increased 3.2 times but it did not change relative to myosin content. The ratio of myosin heavy chain isoforms SM1:SM2 is developmentally regulated and was seen to change from 1.6 at 100 days of gestation to 1.13 at term in normals. After 5 weeks of obstruction SM1:SM2 was 1.27 and it was 1.25 at term, indicating an effect on the developmental regulation of smooth muscle. Rapid fill cystometry in vivo measured the rate of stress relaxation to assess accommodative properties. The half-decay time was increased in all 3 obstructed bladders tested to greater than 15 seconds at 50% capacity (normal less than 5 seconds), suggesting reduced compliance. This study shows that an in utero model of bladder obstruction is feasible. Congenital bladder obstruction produces a variety of structural, biochemical and functional changes in the developing bladder indicative of alterations in the regulation of growth and differentiation.

Microanatomy and morphometry of the hydronephrotic "obstructed" renal pelvis in asymptomatic infants

There has been limited histological study of the obstructed ureteropelvic junction in patients less than 1 year old. We present our prospective studies on the histomorphometry of the ureteropelvic junction complexes of 35 infants, of whom 23 underwent pyeloplasty for obstruction and 12 were age matched autopsy normals. Qualitatively, the major abnormalities of the pelvic microanatomy in the hydronephrotic obstructed kidneys included a lamina muscularis that was significantly thicker than normal and the presence of collagen fibers between muscle fascicles. Additionally, variable amounts of elastin were present in the adventitia and lamina muscularis. At the ureteropelvic junction the abnormalities were an increase in the number of inner longitudinal muscle bundles, collagen between muscle bundles (p less than 0.016) and elastin in the adventitia. Quantitatively, for the pelvis the lamina muscularis was significantly thicker in 18 obstructed kidneys compared to 7 controls (1,075 +/- 79 mu. versus 420 +/- 63 mu., mean +/- standard error of mean, p less than 0.001). The percentage area density of smooth muscle in the obstructed versus normals was increased (45.1% versus 35.2%, p less than 0.039). The percentage area density of collagen in the obstructed specimens versus normal showed an upward trend (38.6% versus 27.6%), which was not significant. In conclusion, the obstructed ureteropelvic junction complexes of kidneys in asymptomatic infants show significant qualitative and quantitative differences from normal.

Quantitative morphometry of the adult human bladder

The primary objective of the present retrospective study was to characterize the effects of aging and BPH on bladder morphometry. Eighty-six bladder specimens were obtained from the autopsy archives of the Milwaukee County Medical Complex. The bladder specimens were divided into 4 groups based upon age and gender: Group I: males between the ages of 35-45 years; Group II: males between the ages of 65-75 years; Group III: females between the ages of 35-45 years; and Group IV: females between the ages of 65-75 years. The age groups were selected in order to identify a group of males with and without BPH. The area density of smooth muscle:connective tissue was determined in bladder specimens using color assisted computer image analysis. Masson-trichrome and double immunoenzymatic staining techniques were used to discriminate the smooth muscle and connective tissue elements of the bladder. The area density of smooth muscle:connective tissue in the Masson-trichrome stained sections was significantly greater in Group I vs. Group II (2.90 +/- 0.22 vs. 2.33 +/- 0.16) and in Group III vs. Group IV (2.85 +/- 0.13 vs. 2.03 +/- 0.20). Aging was associated with a decrease in the area density of smooth muscle:connective tissue ratio in both males and females. The area density of smooth muscle:connective tissue was not significantly different in younger males and females (Group I vs. Group III) and older males and females (Group II vs. Group IV). The present morphometric study suggests that aging and not BPH, is associated with a relative increase in detrusor fibrosis. Infravesical obstruction in BPH may effect bladder function via mechanisms unrelated to the histologic composition of the bladder.

The relative proportion of stromal and epithelial hyperplasia is related to the development of symptomatic benign prostate hyperplasia

The specific features of the prostate adenoma predisposing to the development of symptomatic benign prostatic hyperplasia (BPH) are unknown. Our objective was to determine whether the histological composition of the prostate adenoma is related to the development of symptomatic BPH. Prostate adenomas were obtained from men with asymptomatic BPH undergoing cystoprostatectomy for invasive transitional cell carcinoma, and from men with symptomatic BPH undergoing open prostatectomy, transurethral resection of the prostate and pharmacotherapy. The severity of bladder outlet obstruction was evaluated with the Boyarsky symptom score and uroflowmetry. The percentages of stroma, epithelium and glandular lumen were determined in the prostate adenomas via quantitative image analysis on a computer-assisted morphometry system. The prostate adenomas from the 33 men with symptomatic BPH contained 62 +/- 1%, 15 +/- 1% and 23 +/- 1 of stroma, epithelium and glandular lumen, respectively. The prostate adenomas from 6 men with asymptomatic disease contained 54 +/- 1%, 21 +/- 1% and 25 +/- 1% of stroma, epithelium and glandular lumen, respectively. The ratios of stromal-to-epithelial hyperplasia in the prostate adenomas from men with symptomatic and asymptomatic disease were 4.6 +/- 0.3 and 2.7 +/- 0.1, respectively. The differences in percentage of stroma and epithelium, and the stromal-to-epithelial ratio in the prostate adenomas from men with symptomatic and asymptomatic BPH were statistically significant. Our study suggests that the histological composition of the prostate adenoma is related to the development of symptomatic BPH.

Evaluation of the reported association of obsessive-compulsive symptoms or disorder with Tourette's disorder

This review evaluates the evidence reporting an association of obsessive-compulsive symptoms (OCS) and obsessive-compulsive disorder (OCD) with Tourette's syndrome or disorder (TS). Published reports in the literature describing a relationship between OCS-OCD and TS provided the data for the review. The methodological adequacy of the studies are discussed and rated on five criteria: adequacy of the experimental sample, presence and adequacy of the control sample, whether tics are defined as OCS-OCD, whether blind procedures are used to diagnose OCS-OCD in subjects and controls, and evidence for the reliability and validity of OCS-OCD measures. Although there are considerable clinical indications suggesting an association of OCS-OCD with TS and chronic motor tic disorder (CMT), and a possible overlap between OSC-OCD and TS, our evaluation of the evidence does not provide adequate support for an association between these disorders. To meaningfully evaluate the possible relationship between OCS-OCD and TS requires development of specific criteria for classification of OCS-OCD-TS symptoms, use of adequate experimental and control samples, blind evaluation, reliable and valid measures of OCS-OCD-TS, and appropriate statistical analysis. If such studies are performed, it is possible that the strong relationship reported between OCS-OCD and TS is more likely to be artifact than fact, and recent bandwagon effect rather than the latest breakthrough.

Waiting times for nursing-home placement: the impact of patients' choices

OBJECTIVE

To identify patient characteristics and characteristics of long-term care facilities that significantly affect the waiting time for transfer from hospital to nursing home.

DESIGN

Cohort study.

PARTICIPANTS

All patients designated to be transferred from four Winnipeg hospitals between June 1, 1988, and May 31, 1989. The patients were followed up until placement, death or May 31, 1990.

MAIN OUTCOME MEASURE

Length of time waiting for nursing-home placement and relative rates of placement.

RESULTS

The variable found to shorten the waiting time the most was the patient's choice of a for-profit or nonprofit secular facility; other significant variables were male sex, age of 75 to 84 years and occupancy of an acute care bed during the wait.

CONCLUSION

The province has three policy options: it can increase the proportion of secular nursing-home beds when new facilities are built; it can require that hospital patients accept an interim nursing-home placement pending transfer to the nursing home of their choice; or it can tie the sponsorship of new facilities to a formula based on the ethnoreligious distribution of the population currently aged 55 to 64 years.

Quantifying the Smooth Muscle Content of the Prostate Using Double-Immunoenzymatic Staining and Color Assisted Image Analysis

The primary objective of the present study was to develop a method for quantifying the smooth muscle content of the prostate adenoma. A double immunoenzymatic staining technique was coupled with color assisted image analysis to determine the area density of the smooth muscle within the prostate adenoma. Eight males with symptomatic BPH underwent transrectal biopsy of the prostate. Four micron thick tissue sections were used for the double immunoenzymatic staining process. Rabbit anti-desmin and mouse anti-human prostatic acid phosphatase antibodies were used to selectively bind smooth muscle and prostatic epithelium, respectively. The two different tissue antigens were identified with peroxidase-antiperoxidase (PAP) and alkaline phosphatase-antialkaline phosphatase techniques. The alkaline phosphatase activity and peroxidase activity were developed with fast red and DAB chromogens. The BQ MEG IV Vista color system image analysis was used to discriminate color differences from the stained tissue sections. The thresholds were set to identify smooth muscle (dark brown), epithelium (red), fibrous tissue (pale brown), and glandular lumina (colorless). The mean area density of smooth muscle, fibrous tissue, glandular epithelium, and glandular lumina was 22%, 54%, 16%, and 9%, respectively. The present study suggests that a significant component of the prostate adenoma is smooth muscle. The application of this technique will be utilized to provide further insights into the role of smooth muscle in the pathogenesis and therapy of BPH.

A conical model to describe the nonuniformity of the left ventricular twisting motion

The systolic contraction and fiber shortening in the left ventricle (LV) produces torsional moments in the myocardium, resulting in a gradient of angular displacements about the long axis. This is manifested as a counterclockwise rotation of the apex relative to the base, when viewed from the apex. Recent studies with magnetic resonance imaging (MRI), using noninvasive magnetic tags, have revealed three important properties of the LV twist: (a) The angle of twist (i.e., the angular rotation of a slice relative to the basal slice) is consistently higher at the endocardium as compared to the epicardium; (b) The twist increases towards the apex; and (c) Straight MRI-tagged radial lines at end-diastole (ED) are slightly curved at end-systole (ES), implying a nonlinear transmural variation of the twist. The present study suggests that the geometry of the LV at ES can be represented by a thick-walled hollow cone, and that the transmural twist patterns from ED to ES can be described using the continuum mechanics approach and a small strain analysis of an isotropic cone subjected to external torque. The predicted results are compared with the noninvasive MRI measurements of transmural twist in eight human volunteers. Given the epicardial angles of twist of each slice, the predicted endocardial angles of twist are in good correlation with the experimental findings (r = 0.86, slope = 1.09, SEE = 4.1 degrees). In addition, the model reliably describes the changes in the twist magnitude from apex to base (no significant difference from experimental values, P = 0.2), and predicts the curvilinear pattern at ES of the originally straight ED radial lines. Thus, the conical model with uniform properties of the LV, reliably predicts the nonuniformity of the twist patterns, implying that the LV twist is strongly affected by LV geometry.

The response to alpha blockade in benign prostatic hyperplasia is related to the percent area density of prostate smooth muscle

The objective of the present study was to determine whether the smooth muscle content of the prostate adenoma is related to the clinical response to terazosin, a long-acting selective alpha 1 blocker. Multiple random biopsies of the prostate were obtained from 26 male subjects with symptomatic benign prostatic hyperplasia (BPH) prior to initiating therapy with terazosin. Double immunoenzymatic staining and computer-assisted quantitative color image analysis were utilized to quantify the area density of smooth muscle, connective tissue, glandular epithelium, and glandular lumen. The clinical response to alpha blockade was based upon changes in peak urinary flow rate and the Boyarsky symptom score. A significant direct relationship was observed between the percent area density of smooth muscle and the percent change in peak urinary flow rate. A statistically significant correlation between the percent area density of smooth muscle and the percent change in Boyarsky symptom score was not observed. The percent area density of prostate smooth muscle in the subjects exhibiting a favorable clinical response was 38% greater than the nonresponders (P = 0.068). The clinical response to alpha blockade in BPH is related to the area density of prostate smooth muscle.

Anti-desmin vs. anti-actin for quantifying the area density of prostate smooth muscle

Anti-desmin and anti-actin are commercially available antibodies that bind to smooth muscle. The present study was designed to compare the staining properties of anti-desmin and anti-actin in the human prostate in order to determine the optimal antibody for quantifying the smooth muscle content of the human prostate. Nineteen male subjects with symptomatic BPH underwent needle biopsy of the prostate. Double-immunoenzymatic staining was performed with peroxidase-anti-peroxidase (PAP) and alkaline phosphatase-anti-alkaline phosphatase (APAAP) techniques. Rabbit anti-desmin:mouse anti-human prostatic acid phosphatase and mouse anti-actin:rabbit anti-human prostatic acid phosphatase were utilized. Computer assisted color image analysis was performed using the Bioquant image analysis system. The percent area density of stroma and epithelium was independent of the antibodies used. The percent area density of smooth muscle in the anti-actin stained tissue sections was twofold greater than the anti-desmin stained tissue sections. A direct relationship was observed for the area density of smooth muscle (r = 0.71; P = 0.0006) and the area density of connective tissue (r = 0.82; P less than 0.001) determined from anti-desmin and anti-actin stained tissue sections. Anti-actin represents the optimal antibody for quantifying the area density of prostate smooth muscle. The reproducibility of the immunoenzymatic staining technique is inferred from the direct relationship observed for area density of epithelium between the different staining techniques.