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R Doggweiler

Publications and source records attributed to R Doggweiler.

12 recordsLinked to original sources
PubMed2000

Central nervous system neurons labeled following the injection of pseudorabies virus into the rat prostate gland.

BACKGROUND: The human prostate gland plays an important role in male fertility and is involved in different functional pathologies of the male lower urinary tract (LUT). The role of the prostate in these medical disorders is mainly unknown. Traditional surgical therapeutic attempts often fail to help these patients. For years, the clinical sciences have been stagnating due to a lack of basic science knowledge. Investigations into neuroanatomy and neurophysiology are urgently needed. Therefore, the neuroanatomy of the prostate gland in an experimental setup was explored. Recent progress in neuroscience methodology allows a transneuronal tracing by using a self-amplifying virus tracer, pseudorabies virus (PRV). METHODS: Sixty-two individual adult male Sprague-Dawley rats were used for retrograde transneuronal mapping of the spinal cord and brain stem after PRV-injection and control experiments. A PRV-tracer (5 microl, 1 x 10(8) pfu/ml) was injected into the prostate gland. After a survival time of 72, 96, or 120 hr, the animals were sacrificed. Brain and spinal cord were harvested via a dorsal laminectomy. After cutting on a freezing microtome, the tissue was immunostained for PRV. RESULTS: PRV-positive cells were found within the sacral (S1-S2) and the thoracolumbar (T13-L2) spinal cord. At the supraspinal level, positive cells were found within the following regions: nucleus raphe, lateral reticular formation, nucleus gigantocellularis, A5 noradrenergic cell region, locus coeruleus, pontine micturition center, hypothalamus, medial preoptic region, and periaquaductal gray. CONCLUSIONS: This is the first investigation on the central innervation of the prostate gland showing a broad central representation of neurons involved in the control of the prostate gland. It is obvious, comparing data from the literature, that there is a broad overlap in the innervation of pelvic visceral organs (bladder, rectum, and urethra). The appreciation of these neuroanatomical circumstances allows a growing understanding of common urological pathologies within the pelvis (pelvic pain, lower urinary tract, and bowel dysfunction).

Animals↗
PubMed1999

Sacral nerve stimulation and diurnal urine volume.

OBJECTIVES: During a screening trial to determine candidacy for sacral nerve stimulation (SNS), several patients were required to repeat the baseline dietary because of discrepancies in the 24-hour urine output before and after successful stimulation. This raised a question regarding the relationship between urine production and neuromodulation. A more complete diary analysis of patients affected by urgency/frequency and/or urge incontinence was therefore carried out to evaluate the possibility of a direct modulatory influence of SNS on urine production. METHODS: Voiding diaries of 40 patients (37 females and 3 males, average age 39.4 years) who underwent SNS were evaluated. Voiding diaries were obtained at baseline, during and after peripheral nerve evaluation (PNE) and after permanent implantation. RESULTS: There was an increase in the average volume/void during PNE in 39 patients. Twenty-four-hour urine volume during PNE was statistically greater than that at baseline. Volume/void and diurnal volume were also significantly greater in follow-up periods after permanent implantation. CONCLUSION: SNS appears to influence not only bladder function but also urine production. Increase in volume/void is paralleled by an increase in 24-hour urine output. The mechanism is unclear, but it is consistent with an altered release of antidiuretic hormone. This observation reflects the direct refractory involvement of the hypothalamus in micturition.

Adolescent↗
PubMed1999

Neurourological insights into the etiology of genitourinary pain in men.

PURPOSE: Pelvic pain remains a challenging urological problem. Because antimicrobial therapy is often unsuccessful for relieving symptoms, it is reasonable to question whether pelvic pain is the result of microbiological versus functional pelvic disease. We analyzed clinical and urodynamic findings to evaluate the role of pelvic floor dysfunction in patients with pelvic pain. MATERIALS AND METHODS: We retrospectively evaluated history, physical examination and urodynamic studies in 103 men with an average age of 47 years who presented with pelvic pain between August 1994 and August 1997. In all patients microbiological tests were negative before study entry. RESULTS: The reported locations of pain were the prostate and/or perineal region in 45.6% of cases, scrotum and/or testis in 38.8%, penis in 5.8%, bladder in 5.8%, and lower abdomen and lower back in 1.9% each. Previous treatment consisted of 1 to 12 courses of antibiotics in the preceding 6 to 36 months. In 88.3% of the patients there was pathological tenderness of the striated muscle with poor to absent pelvic floor function. Urodynamics were performed in 84 cases. Cystometry was normal except for decreased compliance in 5 patients. Abnormal findings were mostly evident in the coordination of voiding and in dynamic sphincter-pelvic floor activity. Average sphincter pressure was increased to 104.9 cm. water in 72.6% of the patients, average peak urine flow was decreased to 9.9 ml. per second in 61.9% and functional urethral length was increased to greater than 35 mm. in 79.8%. Urethral profile pattern was dysfunctional, obstructed, and combined dysfunctional and obstructed in 52.4, 11.9 and 21.4% of the cases, respectively, while in 88.1% urethral sensitivity was minimally or markedly increased. CONCLUSIONS: Since activity is a reflection of neural control, the apparent association of pelvic floor dysfunction with pelvic pain raises the probability of a primary or secondary central nervous system breakdown in the regulation of pelvic floor function. This hypothesis is supported by the improvement in symptoms caused by therapy aimed at modulating the pelvic floor, such as biofeedback, medication and sacral anterior root stimulation.

Adult↗
PubMed1998

Botox-induced prostatic involution.

BACKGROUND: A simple approach to induced prostatic atrophy was explored. Surgical denervation is known to produce profound atrophy of the rat prostate. Because Botulinum toxin type A (Botox) produces a long-term chemical denervation, the potential to induce atrophy of the rat prostate was explored. METHODS: Thirty rat prostates were injected with varying doses of Botox. Single and serial injections were used, and rats were subsequently sacrificed after either 1 or 4 weeks, respectively. The prostate glands were harvested, weighed, and histologically studied for morphologic and apoptotic changes. RESULTS: The total prostate volume and weight were found to be reduced in all Botox-injected animals. Histologically, a generalized atrophy of the glands was observed with the H&E stain. There was also diffuse glandular apoptosis evident with the Tunel stain. There were no significant complications (e.g., urinary retention, weight loss, or hind/limb weakness). CONCLUSIONS: Botulinum toxin type A injection into the prostate gland induces selective denervation and subsequent atrophy of the prostate. Apoptosis was seen diffusely throughout the gland. It may be possible that in the future, this long-acting neurotoxin could be used for the treatment of common pathologies of the human prostate.

Animals↗
PubMed1998

Central autonomic innervation of the lower urinary tract--a neuroanatomy study.

Knowledge about the central innervation of the lower urinary tract is limited. The spinal cord and the pontine micturition center have been investigated most thoroughly, whereas high centers have received little attention. Pseudorabies virus (PRV), a self-amplifying and transneuronal tracer was injected into the bladder trigone of 21 Sprague-Dawley rats. The animals were killed after 72, 96, and 120 h. The whole CNS was sectioned and immunostained for PRV. CNS centers directly connected to the bladder include the intermedio lateral cell column, the central autonomic nucleus, and the nucleus intercalatus at the spinal cord levels T12-L2 and L6-S2. The raphe pallidus et magnus, the A5 nor-adrenergic area, the pontine micturition center, the locus coeruleus, the periaquaductal gray, the nucleus para- et periventricularis of the hypothalamus, the red nucleus, the medial preoptic area, and the cortex are supraspinal centers connected to the bladder. Lower urinary tract function is a complex multilevel and multineuronal interaction. It involves facilitation and inhibition at many levels of the CNS.

Animals↗
PubMed1998

Postoperative chronic pain and bladder dysfunction: windup and neuronal plasticity--do we need a more neurological approach in pelvic surgery?

PURPOSE: Cases of combined symptoms of dysfunctional voiding and associated pelvic discomfort are difficult diagnostic and therapeutic challenges. Surgical solutions not uncommonly fail to relieve those symptoms. We determine why these symptoms persist postoperatively. MATERIALS AND METHODS: Four cases of ureteral injury during gynecological laparoscopic procedures for pelvic/menstrual pain are presented. The cases are reviewed for their severity and similarity in presenting symptoms, complications and long-term consequences. RESULTS: In all cases light pain symptoms and/or dysfunctional voiding problems that existed before the initial surgery escalated severely after corrective pelvic surgery. CONCLUSIONS: There are established neurophysiological mechanisms that would explain the observed increase in pain after surgical manipulation of the pelvis. Windup and changes in neuronal plasticity are direct consequences of wounding and/or neural injury to the central nervous system. These principles are important for surgeons to appreciate due to the impact they can have on the outcomes of surgery. Blocking the sensory input into the spinal cord, inherent to every surgical procedure, through use of local anesthetics, that is preemptive anesthesia, before creation of a wound provides the greatest protection against escalation of symptoms. Thorough evaluation of all patients before pelvic surgery is recommended to identify high risk groups (preexisting pain, voiding syndromes).

Adult↗
PubMed1998

Neurostimulation and neuromodulation: a guide to selecting the right urologic patient.

Sensory input has an important influence on the integrity of neural circuitry. Central nervous system circuitry is programmed and reinforced by everyday experience. Even the simplest of behaviors participate in this process. A balance between inhibition and facilitation must be maintained for the CNS to function normally. For example, the bladder stores urine because of the inhibition from a closed sphincter, and relaxation of the sphincter disinhibits the bladder to permit voiding. This synergistic 'seesaw' in reflex neural activity preserves the functional and anatomical integrity of the lower urinary tract. Dysfunction and anatomical change results when an unnatural bias develops between inhibitory and facilitatory neural activity. Neurostimulation has an inherent conditioning effect on neural excitability and can restore the neural equilibrium. Voiding diaries are very useful in documenting these changes.

Electric Stimulation Therapy↗
PubMed1998

Neurogenically mediated cystitis in rats: an animal model.

PURPOSE: Pseudorabies virus (PRV) is a useful tool for mapping the control circuitry of the spinal cord. In the process of mapping CNS regulatory pathways for the lower urinary tract, a hemorrhagic change in the bladder was observed that was not overtly evident in other pelvic organs. The relationship between the appearance of hemorrhagic changes in the bladder and the evolution of PRV induced changes in the spinal cord was therefore explored. MATERIALS AND METHODS: Sprague-Dawley rats were injected with PRV into the ACD tail-muscle. Bladder and CNS fixation were achieved by transcardial perfusion with formaldehyde. Multi-level sections were obtained from T8 through S4. Fixed tissue was stained and evaluated by light microscopy. Immunohistochemical stains were carried out for PRV and iNOS on spinal cord tissue. We were therefore able to evaluate the relationship between the manifestation of the hemorrhagic cystitis, appearance of the PRV in the spinal cord and evidence of CNS inflammation. RESULTS: The evolution of hemorrhagic cystitis paralleled the evidence of inflammation in the thoraco-lumbar and sacral cord. These bladders contained 5 to 9 ml. of bloody urine (a normal rat bladder contains 1 to 2 ml.). On cystomanometry (CMG) the bladders were acontractile. No PRV could be cultured in the hemorrhagic bladders. The histological changes observed in the bladder represent true inflammation. CONCLUSION: There was no obvious explanation for these changes other than the associated inflammatory changes in the spinal cord. The findings are consistent with the hypothesis that a spinal cord stress, via an unknown metabolic pathway, can result in dramatic, neurogenically mediated changes in the bladder.

Animals↗
PubMed1997

Renal transplantation following reduction of ileocecocystoplasty performed 9 years earlier for undiversion.

A case of complex urinary tract reconstruction is reported. Reduction of ileocecocystoplasty, performed in a young boy for undiversion, was necessary together with native binephrectomy before renal transplantation 9 years later. Transplantation was successfully performed after cystoplasty volume reduction and decrease of outlet resistance obtained with unilateral TUIP. Enterocystoplasty is a reasonable option for bladder rehabilitation in patients requiring renal transplantation for end-stage renal disease caused by lower tract dysfunction.

Adolescent↗