“Catching Cannonballs”: Reflections on a career as a History Teacher

This essay was delivered as a plenary address at a conference for high school teachers on teaching history in Maine, held October 1997 at the University of Maine. Retiring History Professor Jerome Nadelhaft reflects on his career as colonial historian at the University of Maine and suggests that the mission of the history teacher is to impart an ethical sensibility to students

Oral Interview of Diane Elze by Ruth Nadelhaft Interviewer for the Feminist Oral History Project

Part of a series of interviews conducted for the Feminist Oral History Project during 1992 by Ruth Nadelhaft concerning the history of Spruce Run.https://digitalcommons.library.umaine.edu/maine_women_audio/1032/thumbnail.jp

Effects of two atypical neuroleptics, olanzapine and risperidone, on the function of the urinary bladder and the external urethral sphincter in anesthetized rats

BACKGROUND: A previous report showed that the atypical neuroleptic clozapine resulted in marked changes in urodynamic parameters and greatly inhibited the activity of the external urethral sphincter in anesthetized rats. Such findings may help explain the high incidence of urinary disturbances reported during clozapine therapy. In an effort to extend our observations to other atypical neuroleptic agents, the present study investigated the effects of two newer atypical antipsychotics, olanzapine and risperidone, on the bladder and external urethral sphincter during cystometry in anesthetized rats. RESULTS: At a dose of 0.1 mg/kg (i.v.), olanzapine decreased the micturition volume and increased the residual volume. In addition, olanzapine decreased the expulsion time and the amplitude of the high frequency oscillations observed during the expulsion phase. Larger doses (1 mg/kg) had a greater effect. Olanzapine also reduced the activity recorded from the external urethral sphincter, and the bursting observed during the expulsion phase was abolished by 1.0 mg/kg. Risperidone had similar effects although the maximal effects were smaller than those observed with olanzapine. The amplitude of bladder contractions elicited by electrical stimulation of the pelvic nerve was reduced by olanzapine but not risperidone suggesting a possible anti-muscarinic peripheral effect of olanzapine. CONCLUSIONS: Olanzapine and risperidone significantly altered several voiding parameters and decreased the activity of the external urethral sphincter in the anesthetized rat. We propose that these effects are due to the central action of these drugs and not to peripheral effects. These findings may explain some of the clinical reports of urinary incontinence with risperidone and may predict similar occurrences with olanzapine therapy

Separate urinary bladder and prostate neurons in the central nervous system of the rat: simultaneous labeling with two immunohistochemically distinguishable pseudorabies viruses

BACKGROUND: This work examines the central nervous system distribution of virus-labeled neurons from the rat urinary bladder and the prostate simultaneously within the same tissue sections. Two immunohistochemically distinct pseudorabies virus strains were simultaneously injected into male Sprague Dawley rats (~280 gm). One virus was injected into the bladder and the other into the prostate. After incubation intervals of 2.25, 2.5, 2.75, 3 and 4 days, sections from the spinal cord and brain were processed immunohistochemically to detect cells, within a single section, which were labeled separately by each virus or were labeled by both viruses. RESULTS: Each strain of virus labeled a separate population of neurons and some neurons were labeled by both strains. The majority of neurons labeled by virus from the urinary bladder were found in the L6-S1 spinal cord segments within the dorsal gray commissure, the intermediolateral area and the superficial dorsal horn. Neurons labeled by virus from the prostate were mainly found in the L1-L2 spinal cord segments in the dorsal gray commissure and the intermediolateral areas. Double-labeled interneurons in L1-L2 were mainly located in the intermediolateral area. In L6-S1 they were divided between the dorsal gray commissure and the intermediolateral area. CONCLUSIONS: Spinal neurons innervating the bladder are clearly separate and different from those innervating the prostate. This difference also persists in the brain. In disagreement with previous reports, no direct anatomical evidence of parasympathetic innervation of the prostate was observed

Central effects of clozapine in regulating micturition in anesthetized rats

BACKGROUND: We previously showed that systemic administration of the atypical neuroleptic clozapine in the rat altered a number of urodynamic variables and inhibited the external urethral sphincter. Since clozapine acts at several receptor types both at the periphery and the central nervous system, the site of action remained uncertain. Therefore, the purpose of this study was to determine the effects of central administration of clozapine on the bladder and the external urethral sphincter during cystometry and to examine differences in spinal versus supraspinal administration. We extended our observations by delivering clozapine centrally in anesthetized rats instrumented with either an intrathecal (L6-S1 spinal segment) or an intracerebroventricular (lateral ventricle) catheter. RESULTS: Clozapine decreased micturition volume and increased residual volume possibly by acting at a supraspinal site. Expulsion time and amplitude of the high frequency oscillations were reduced by clozapine possibly by acting at a spinal site. Bladder capacity was increased after central clozapine but probably due to a peripheral effect. Clozapine acting at spinal and supraspinal sites increased pressure threshold. Contraction time and peak pressure were not affected by clozapine. The EMG from the external urethral sphincter was also reduced following clozapine centrally and suggests a spinal and a supraspinal site of action. CONCLUSIONS: The results from the present study suggest that spinal and supraspinal central sites mediate clozapine's action in inhibiting expulsion parameters and the external urethral sphincter of the rat. Therefore, the reduction in the voiding efficiency observed after clozapine appears to be mediated by spinal and supraspinal sites

Book Reviews

Reviews of the following books: Joe Scott, The Woodsman-Songmaker by Edward D. Ives; Legacy of a Lifetime: The Story of Baxter State Park by John W. Hakola; General William King: Merchant, Shipbuilder, and Maine\u27s First Governor by Marion Jaques Smith; Picture History of New England Passenger Vessels by W. Bartlett Cram; Colonial Massachusetts: A History by Benjamin Labaree

c-fos Expression in Bladder-Specific Spinal Neurons after Spinal Cord Injury Using Pseudorabies Virus

PURPOSE: c-fos expression in spinal neurons that are activated by lower urinary tract stimulation are not organ specific. In this experiment, we demonstrated changes of c-fos expression in bladder-specific preganglionic neurons (PGNs) and interneurons using pseudorabies virus (PRV). MATERIALS AND METHODS: Forty Sprague-Dawley rats were used. We identified the neuronal pathway associated with the bladder by injecting PRV into the detrusor. An immunohistochemical method was used to stain Fos-protein encoded by the c-fos gene. Immunofluorescent staining for PRV was performed to evaluate changes in bladder-specific spinal neurons. RESULTS: Immunofluorescent staining with choline acetyltransferase (ChAT) revealed that the sacral parasympathetic nucleus (SPN) regions contained 9.8 PGNs/ section. In rats with chronic spinal cord injury by intravesical saline instillation, 82.4+/-10.3% of PGNs in SPN exhibited Fos-immunoreactive (IR). Two and a half days after PRV infection, PRV-IR PGNs were observed at 5.4 PGNs/ section, and 2.7+/-1.6% of them exhibited Fos-IR. Unlike ChAT-IR PGNs, PRV-IR PGNs are bladder-specific neurons and PRV-IR and Fos-IR cells found in the back of PRV-IR PGNs are bladder- specific interneurons. Three days after PRV infection, we observed many PRV-IR and Fos-IR cells in the dorsal commissure. These neurons are interneurons distributed in the bladder. CONCLUSION: We confirmed that in chronic spinal cord injury, the patterns of c-fos expression in bladder-specific spinal neurons were similar to those in voiding-reflex related spinal neurons, which had already been demonstrated earlier. We believe that our methodology can be applied to study interactions between voiding and other organs as well, such as the urethra and prostate.ope

Nuclear expression of PG-21, SRC-1, and pCREB in regions of the lumbosacral spinal cord involved in pelvic innervation in young adult and aged rats

In rats, ageing results in dysfunctional patterns of micturition and diminished sexual reflexes that may reflect degenerative changes within spinal circuitry. In both sexes the dorsal lateral nucleus and the spinal nucleus of the bulbospongiosus, which lie in the L5-S1 spinal segments, contain motor neurons that innervate perineal muscles, and the external anal and urethral sphincters. Neurons in the sacral parasympathetic nucleus of these segments provide autonomic control of the bladder, cervix and penis and other lower urinary tract structures. Interneurons in the dorsal gray commissure and dorsal horn have also been implicated in lower urinary tract function. This study investigates the cellular localisation of PG-21 androgen receptors, steroid receptor co-activator one (SRC-1) and the phosphorylated form of c-AMP response element binding protein (pCREB) within these spinal nuclei. These are components of signalling pathways that mediate cellular responses to steroid hormones and neurotrophins. Nuclear expression of PG-21 androgen receptors, SRC-1 and pCREB in young and aged rats was quantified using immunohistochemistry. There was a reduction in the number of spinal neurons expressing these molecules in the aged males while in aged females, SRC-1 and pCREB expression was largely unchanged. This suggests that the observed age-related changes may be linked to declining testosterone levels. Acute testosterone therapy restored expression of PG-21 androgen receptor in aged and orchidectomised male rats, however levels of re-expression varied within different nuclei suggesting a more prolonged period of hormone replacement may be required for full restoratio

A Pivotal Role of Lumbar Spinothalamic Cells in the Regulation of Ejaculation via Intraspinal Connections

Introduction.  A population of lumbar spinothalamic cells (LSt cells) has been demonstrated to play a pivotal role in ejaculatory behavior and comprise a critical component of the spinal ejaculation generator. LSt cells are hypothesized to regulate ejaculation via their projections to autonomic and motor neurons in the lumbosacral spinal cord. Aim.  The current study tested the hypothesis that ejaculatory reflexes are dependent on LSt cells via projections within the lumbosacral spinal cord. Methods.  Male rats received intraspinal injections of neurotoxin saporin conjugated to substance P analog, previously shown to selectively lesion LSt cells. Two weeks later, males were anesthetized and spinal cords were transected. Subsequently, males were subjected to ejaculatory reflex paradigms, including stimulation of the dorsal penile nerve (DPN), urethrogenital stimulation or administration of D3 agonist 7‐OH‐DPAT. Electromyographic recordings of the bulbocavernosus muscle (BCM) were analyzed for rhythmic bursting characteristic of the expulsion phase of ejaculation. In addition, a fourth commonly used paradigm for ejaculation and erections in unanesthetized, spinal‐intact male rats was utilized: the ex copula reflex paradigm. Main Outcome Measures.  LSt cell lesions were predicted to prevent rhythmic bursting of BCM following DPN, urethral, or pharmacological stimulation, and emissions in the ex copula paradigm. In contrast, LSt cell lesions were not expected to abolish erectile function as measured in the ex copula paradigm. Results.  LSt cell lesions prevented rhythmic contractions of the BCM induced by any of the ejaculatory reflex paradigms in spinalized rats. However, LSt cell lesions did not affect erectile function nor emissions determined in the ex copula reflex paradigm. Conclusions.  These data demonstrate that LSt cells are essential for ejaculatory, but not erectile reflexes, as previously reported for mating animals. Moreover, LSt cells mediate ejaculation via projections within the spinal cord, presumably to autonomic and motor neurons. Staudt MD, Truitt WA, McKenna KE, de Oliveira CVR, Lehman MN, and Coolen LM. A pivotal role of lumbar spinothalamic cells in the regulation of ejaculation via intraspinal connections. J Sex Med 2012;9:2256–2265.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93690/1/j.1743-6109.2011.02574.x.pd