RESUMEN
Bladder afferent outflow, linked to sensation, plays a critical role in bladder pathology: abnormal outflow results in altered sensation, leading to increased voiding frequency, urge and often incontinence. ß3-adrenoceptor agonists have been suggested to be beneficial in treating these symptoms. However, the absence of a significant sympathetic innervation of the detrusor and only a modest relaxation of bladder muscle by ß3 agonists has questioned the therapeutic site of action of ß3 agonists in the bladder. The present study was done to explore the possibility that ß3-adrenoceptors might be located in the pelvic plexus. Using the rat, where the pelvic plexus is located primarily within a single ganglion, the major pelvic ganglion (MPG), immuno-histochemical approaches were used to identify structures expressing ß3-adrenoceptor immuno-reactivity (ß3AR-IR). The only structures found to express ß3AR-IR were small-diameter tyrosine hydroxylase and vesicular mono-amine transporter immuno-reactive (TH-IR and vmat-IR) neurones. These neurones, found in clusters or singly on the periphery of the ganglion, or dispersed in smaller clumps throughout the MPG, are similar to the small intensely fluorescent (SIF) cells described previously. Not all small cells expressed ß3AR-IR. A population of the small cells were also immuno-reactive to the type 3 muscarinic receptor (M3R-IR) and the P2X3 purinergic receptor (P2X3-IR). Clumps of small cells were associated with calcitonin gene-related peptide immuno-reactive (CGRP-IR) nerve fibres (putative sensory fibres) and a small number were contacted by putative cholinergic nerves expressing immuno-reactivity to vesicular acetylcholine transporter (vacht-IR). These observations are consistent with the idea that small cells are interneurons and one of the components making up complex neural circuits within the MPG. The precise physiological role of these neural elements in the MPG is unknown. However, as one therapeutic action of ß3-adrenoceptor agonists is to modulate sensation, it is possible that these neural circuits may be involved in the regulation of afferent outflow and sensation.
Asunto(s)
Plexo Hipogástrico/metabolismo , Receptor Muscarínico M3/metabolismo , Receptores Adrenérgicos beta 3/metabolismo , Vejiga Urinaria/inervación , Animales , Anticuerpos Monoclonales/farmacología , Plexo Hipogástrico/enzimología , Plexo Hipogástrico/inmunología , Inmunohistoquímica , Interneuronas/enzimología , Interneuronas/inmunología , Interneuronas/metabolismo , Masculino , Ratas Wistar , Receptor Muscarínico M3/inmunología , Receptores Adrenérgicos beta 3/inmunología , Tirosina 3-Monooxigenasa/inmunología , Tirosina 3-Monooxigenasa/metabolismo , Proteínas de Transporte Vesicular de Monoaminas/inmunología , Proteínas de Transporte Vesicular de Monoaminas/metabolismoRESUMEN
Immunohistochemical characteristics of neurones innervating the porcine uterus located in paracervical ganglia were studied with a combination of retrograde fluorescent tracing and immunofluorescence. Retrograde fluorescent tracer Fast Blue (FB) was injected into the uterine horn and uterine cervix. The presence of biologically active substances, tyrosine hydroxylase (TH), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), galanin (GAL), Met-enkephalin-Arg-Gly-Leu (MEAGL) and calcitonin gene-related peptide (CGRP) was studied in FB-positive neurones localised in paracervical ganglia. FB-positive neurones containing TH, NPY, VIP and MEAGL were numerous, while those containing CGRP were scarce. The results pointed to some species-related differences in immunohistochemical coding of neurones of paracervical ganglion responsible for uterus innervation.
Asunto(s)
Encefalina Metionina/análogos & derivados , Plexo Hipogástrico/citología , Neuronas/química , Útero/inervación , Animales , Péptido Relacionado con Gen de Calcitonina/análisis , Encefalina Metionina/análisis , Femenino , Galanina/análisis , Plexo Hipogástrico/química , Plexo Hipogástrico/enzimología , Inmunohistoquímica , Neuronas/enzimología , Neuropéptido Y/análisis , Porcinos , Tirosina 3-Monooxigenasa/análisis , Péptido Intestinal Vasoactivo/análisisRESUMEN
The present study was aimed at disclosing the distribution of paracervical neurons projecting to the ampulla and isthmus of the porcine oviduct and the pattern(s) of co-existence of tyrosine hydroxylase (TH), dopamine beta-hydroxylase (D beta H), neuropeptide Y (NPY), substance P (SP), calcitonin gene-related peptide (CGRP) and nitric oxide synthase (NOS) within these nerve cell bodies. The fluorescent retrograde tracer Fast Blue (FB) was injected into the wall of the ampullar (n = 3) and isthmal (n = 3) part of the organ in six sexually immature female pigs. After a survival period of three weeks paracervical ganglia (PCG) were collected. 10 microns-thick cryostat sections of the ganglia were examined for the presence of FB-positive (FB+) nerve cells under the fluorescent microscope. Tracered neurons were counted in every third section and processed for double-labelling immunofluorescence according to the method of Wessendorf and Elde. 78.6% of FB+ neurons were projecting to the isthmus while 21.4% of the studied population innervated the ampulla of the oviduct. Double-labelling immunofluorescence revealed the existence of the following different chemically coded subpopulations of the studied perikarya: TH+/D beta H+, TH+/NPY+, TH+/NOS+, TH+/NOS-, SP-/NOS+, SP+/CGRP+.
Asunto(s)
Trompas Uterinas/inervación , Plexo Hipogástrico/citología , Neuronas/química , Neuronas/enzimología , Animales , Péptido Relacionado con Gen de Calcitonina/análisis , Dopamina beta-Hidroxilasa/análisis , Femenino , Plexo Hipogástrico/química , Plexo Hipogástrico/enzimología , Inmunohistoquímica , Neuropéptido Y/análisis , Óxido Nítrico Sintasa/análisis , Sustancia P/análisis , Porcinos , Tirosina 3-Monooxigenasa/análisisRESUMEN
The presence of NADPH-diaphorase activity and acetylcholinesterase in the testis, epididymis, vas deferens, seminal vesicle, pelvic plexus, prostate and urethra of man and guinea-pig was investigated with the nitro blue NADPH technique and the thiocholine method, respectively. In human material NADPH-diaphorase activity was found in the Leydig cells, Sertoli cells and the epithelial linings of the rete testis, the excretory ducts, seminal vesicle, prostate and urethra. The guinea-pig material showed staining of the Leydig cells and spermatozoa and similar epithelial staining of the tract as man. Nerves beneath the epithelium and in the muscle layers of cauda epididymis, vas deferens, seminal vesicle, prostate and urethra were also stained. NADPH-diaphorase-positive nerve cells were seen in the pelvic plexus. Some cells also displayed acetylcholinesterase activity but others showed activity for only one of the enzymes or no activity for either enzyme. In the cauda epididymis, vas deferens, seminal vesicle, prostate and urethra acetylcholinesterase-positive nerve fibres formed a plexus beneath the secretory cells. It is concluded that NADPH-diaphorase, generally accepted as a nitric oxide synthase, is present in glandular cells of the male genital tract. The enzyme is also present in nerves, where it is partly co-localized with acetylcholinesterase.
Asunto(s)
Acetilcolinesterasa/metabolismo , Genitales Masculinos/enzimología , NADPH Deshidrogenasa/metabolismo , Animales , Epidídimo/enzimología , Genitales Masculinos/citología , Genitales Masculinos/inervación , Cobayas , Histocitoquímica , Humanos , Plexo Hipogástrico/enzimología , Masculino , Próstata/enzimología , Vesículas Seminales/enzimología , Especificidad de la Especie , Testículo/enzimología , Uretra/enzimología , Conducto Deferente/enzimologíaRESUMEN
Expression and androgen regulation of the gene for neuronal nitric oxide synthase (NOS I) were examined in neurons of the major pelvic ganglia in male rats. Some of these postganglionic neurons innervate the penis and produce nitric oxide, which is believed to play a major role in penile erection. Rats were either castrated or sham operated and implanted with SILASTIC brand capsules filled with powdered testosterone (T) or 5alpha-dihydrotestosterone (5alphaDHT) or left empty. After 4 days, the number of neurons intensely stained for NADPH-diaphorase as well as those giving a NOS I signal in in situ hybridization experiments increased in castrated rats treated with testosterone by 31% and 42%, respectively, relative to those in untreated castrated rats. This suggests that the increase in NADPH-diaphorase activity resulted from enzyme synthesis and was due to a modification of NOS I messenger RNA (mRNA) accumulation. After 7 days, Northern blot analysis showed that castration produced a decrease in the amount of NOS I mRNA relative to that of ribosomal RNA. This decrease was almost prevented by T treatment. No significant differences were observed by reverse transcriptase-PCR between 7-day and 28-day treatments. However, in 7-day castrated rats treated with 5alphaDHT, NOS I signals relative to those of hypoxanthine phosphoribosyltransferase, taken as reference, were significantly higher than those in castrated rats and resembled those in sham-castrated rats, suggesting that 5alphaDHT was probably more potent than testosterone in preventing the decrease in NOS I mRNA levels elicited by castration. These results show that NOS I can be positively regulated by androgens and are consistent with the suggestion that these steroids play a role in the physiological processes of penile erection.
Asunto(s)
Andrógenos/farmacología , Ganglios Autónomos/citología , Plexo Hipogástrico/citología , Neuronas/enzimología , Óxido Nítrico Sintasa/genética , ARN Mensajero/análisis , Animales , Secuencia de Bases , Northern Blotting , Cartilla de ADN/análisis , Cartilla de ADN/química , Cartilla de ADN/genética , Dihidrotestosterona/farmacología , Ganglios Autónomos/química , Ganglios Autónomos/enzimología , Regulación Enzimológica de la Expresión Génica , Plexo Hipogástrico/química , Plexo Hipogástrico/enzimología , Hibridación in Situ , Masculino , NADPH Deshidrogenasa/análisis , Neuronas/metabolismo , Orquiectomía , Reacción en Cadena de la Polimerasa , ARN Mensajero/química , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Testosterona/farmacologíaRESUMEN
By the indirect immunofluorescence method, the distribution of nitric oxide synthase (NOS)-like immunoreactivity (LI) and its possible colocalization with neuropeptide immunoreactivities, with two enzymes for the catecholamine synthesis pathway, tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH), as well as the enzyme for the acetylcholine synthesis pathway, choline acetyltransferase (ChAT) were studied in the anterior pelvic ganglion (APG), the inferior mesenteric ganglion (IMG) and the hypogastric nerve in the male guinea pig. The analyses were performed on tissues from intact animals, as well as after compression/ligation or cut of the hypogastric nerve. In some cases the colonic nerves were also cut. Analysis of the APG showed two main neuronal cell populations, one group containing NOS localized in the caudal part of the APG and one TH-positive group lacking NOS in its cranial part. The majority of the NOS-positive neurons contained ChAT-LI. Some NOS-positive cells did not contain detectable ChAT, but all ChAT-positive cells contained NOS. NOS neurons often contained peptides, including vasoactive intestinal peptide (VIP), neuropeptide tyrosine (NPY), somatostatin (SOM) and/or calcitonin gene-related peptide (CGRP). Some NOS cells expressed DBH, but never TH. The second cell group, characterized by absence of NOS, contained TH, mostly DBH and NPY and occasionally SOM and CGRP. Some TH-positive neurons lacked DBH. In the IMG, the NOS-LI was principally in nerve fibers, which were of two types, one consisting of strongly immunoreactive, coarse, varicose fibers with a patchy distribution, the other one forming fine, varicose, weakly immunoreactive fibers with a more general distribution. In the coarse networks, NOS-LI coexisted with VIP- and DYN-LI and the fibers surrounded mainly the SOM-containing noradrenergic principal ganglion cells. A network of ChAT-positive, often NOS-containing nerve fibers, surrounded the principal neurons. Occasional neuronal cell bodies in the IMG contained both NOS- and ChAT-LI. Accumulation of NOS was observed, both caudal and cranial, to a crush of the hypogastric nerve. VIP accumulated mainly on the caudal side and often coexisted with NOS. NPY accumulated on both sides of the crush, but mainly on the cranial side, and ENK was exclusively on the cranial side. Neither peptide coexisted with NOS. Both substance P (SP) and CGRP showed the strongest accumulation on the cranial side, possibly partly colocalized with NOS. It is concluded that the APG in the male guinea-pig consists of two major complementary neuron populations, the cholinergic neurons always containing NOS and the noradrenergic neurons containing TH and DBH. Some NOS neurons lacked ChAT and could represent truly non-adrenergic, non-cholinergic neurons. In addition, there may be a small dopaminergic neuron population, that is containing TH but lacking DBH. The cholinergic NOS neurons contain varying combinations of peptides. The noradrenergic population often contained NPY and occasionally SOM and CGRP. It is suggested that NO may interact with a number of other messenger molecules to play a role both within the APG and IMG and also in the projection areas of the APG.
Asunto(s)
Colina O-Acetiltransferasa/metabolismo , Ganglios Autónomos/química , Ganglios Autónomos/enzimología , Plexo Hipogástrico/química , Plexo Hipogástrico/enzimología , Neuropéptidos/análisis , Óxido Nítrico Sintasa/metabolismo , Animales , Catecolaminas/biosíntesis , Dopamina beta-Hidroxilasa/metabolismo , Técnica del Anticuerpo Fluorescente Indirecta , Cobayas , Masculino , Microscopía Fluorescente , Neuronas/enzimología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Distribution of neuronal nitric oxide synthase-immunoreactive (nNOS-IR) nerve fibers and somata in the rat epididymis and major pelvic ganglia was studied by immunohistochemical methods. In the epididymis, the supply of nNOS-IR fibers was highest in the cauda and became progressively fewer toward the caput. In the cauda and corpus, nNOS-IR fibers were distributed throughout the subepithelial tissues and around the epithelial. The pattern of distribution of vasoactive intestinal polypeptide (VIP)- and tyrosine hydroxylase (TH)-immunoreactive fibers in the epididymis was similar but the latter was generally more numerous in a given region as compared to that of nNOS-IR fibers. A population of neurons in the major pelvic ganglia were nNOS-IR-, TH- or VIP-IR. Double-labeling studies revealed that few neurons in the major pelvic ganglia contained both nNOS-IR and TH-IR. Whereas nNOS-IR and VIP-IR appeared to co-localize in the same population of the pelvic ganglion cells. Similarly, nNOS-IR fibers in the epididymis were mostly VIP-positive and TH-negative. Unilateral injection of the fluorescent tracer Fluorogold into the junction between the vas deferens and the cauda labeled a population of neurons in the right and left major pelvic ganglia, some of which were also nNOS-IR. A small number of dorsal root ganglion cells contained Fluorogold and very few expressed NOS-IR. It may be concluded that nNOS-IR nerve fibers in the rat epididymis arise mainly from neurons in the major pelvic ganglia the major of which express VIP-IR but not TH-IR. The extensive supply of nNOS-immunoreactive fibers around the epithelium and throughout the subepithelial tissues suggests that NO may be closely associated with smooth muscle contraction.
Asunto(s)
Epidídimo/enzimología , Fibras Nerviosas/enzimología , Neurotransmisores/análisis , Óxido Nítrico Sintasa/análisis , Estilbamidinas , Animales , Colorantes Fluorescentes , Ganglios Espinales/citología , Ganglios Espinales/enzimología , Plexo Hipogástrico/citología , Plexo Hipogástrico/enzimología , Inmunohistoquímica , Masculino , Neuronas/enzimología , Fenotipo , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/análisis , Péptido Intestinal Vasoactivo/análisisRESUMEN
Neurones in the ureterovesical ganglion complex provide autonomic innervation to the pelvic ureter, the ureterovesical junction and the bladder trigone. We examined the distribution and peptide co-expression pattern of nitric oxide synthase (NOS) in the human ureterovesical ganglia by combining NADPH-diaphorase histochemistry with immunoreactivity for vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP). Less than 20% of nerve cells in the large ganglia of the ureterovesical complex were stained for NOS activity. In elderly individuals, ganglion cells regularly exhibited conspicuous morphological alterations suggestive of degenerative changes. Most of the NOS-positive cell bodies costained for VIP-immunoreactivity. A minority of NOS-expressing cells also reacted for NPY-immunoreactivity. CGRP-immunoreactivity was present in varicose terminal-like nerve fibres which were found to encircle NOS-containing perikarya. Occasionally, NOS-positive somata were surrounded by plexiform axon terminals which immunostained for VIP or NPY. We conclude that the passage of urine across the ureterovesical junction is under relaxatory control of a local nitric oxide/VIP(NPY) pathway which may be modulated by preganglionic efferent and/or primary afferent input.
Asunto(s)
Ganglios Autónomos/enzimología , Plexo Hipogástrico/enzimología , NADPH Deshidrogenasa/análisis , Neuropéptidos/análisis , Uréter/inervación , Adulto , Anciano , Péptido Relacionado con Gen de Calcitonina/análisis , Femenino , Técnica del Anticuerpo Fluorescente Directa , Ganglios Autónomos/química , Humanos , Plexo Hipogástrico/química , Masculino , Persona de Mediana Edad , Neuropéptido Y/análisis , Óxido Nítrico Sintasa/metabolismo , Distribución Tisular , Péptido Intestinal Vasoactivo/análisisRESUMEN
OBJECTIVE: To determine the effect of diabetes mellitus (DM) on erectile function and evaluate the levels of nitric oxide synthetase (NOS) activity in streptozotocin-induced diabetic rats. MATERIALS AND METHODS: Rats were studied at 9 weeks and 14 weeks after the induction of DM by streptozotocin and compared with untreated control rats. Erectile potency was assessed physiologically by testing and recording mating behaviour. NOS activity was assayed in penile tissues and major pelvic ganglia (MPG) by conversion of [3H] L-arginine to [3H] citrulline. Histological, ultrastructural and immunohistochemical studies of penile tissues were performed in similar groups of rats. RESULTS: Diabetes mellitus adversely and significantly degraded all parameters of mating behaviour, thus indicating defective erectile potency. However, NOS activities in penile tissues from both groups of diabetic rats were significantly higher than those in controls (P < 0.01). In MPG, NOS activities were not significantly different between diabetic and control rats (P > 0.05). Histological, ultrastructural and immunohistochemical studies of penile tissues revealed no significant differences between control and diabetic rats, indicating an intact effector organ (smooth muscles) in rats with up to 14 weeks of DM. CONCLUSION: The impotence frequently observed in diabetic subjects would suggest that despite the increase in NOS activity in the penis, the pharmacological action of nitric oxide is impaired.
Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Diabetes Mellitus Experimental/enzimología , Plexo Hipogástrico/enzimología , Pene/enzimología , Animales , Diabetes Mellitus Experimental/patología , Inmunohistoquímica , Masculino , Óxido Nítrico Sintasa , Pene/inervación , Pene/ultraestructura , Ratas , Ratas Sprague-Dawley , Conducta Sexual AnimalRESUMEN
Age-differences in the sensitivity of peripheral sympathetic neurons to chronic ethanol exposure and ethanol withdrawal were studied in male Wistar rats aged 4 months, 12 months, or 24 to 25 months. The superior cervical ganglia (SCG) of the young (4 months) and the 2-year-old rats responded to a 12-day or 4-week ethanol exposure with significantly increased catecholamine turnover, while the ganglia of the middle-aged rats (12 months) showed only a minor increase in the intensity of catecholamine fluorescence and tyrosine hydroxylase immunoreactivity. Extensive neuronal vacuolation was found in the 4 months ethanol-exposed SCG, probably as a reaction of a subpopulation of neurons to increased stimulation. Ethanol-induced neuronal loss was most prominent in the SCG of the oldest age group. Contrary to the marked changes in SCG functional and morphometric parameters, the pelvic sympathetic neurons in the hypogastric ganglion showed no significant changes after ethanol exposure. The pattern of ethanol-induced morphological alterations found in the present study did not provide unambiquous support for either the "accelerated aging" or the "increased vulnerability" concept regarding ethanol-aging interactions in the nervous system.
Asunto(s)
Envejecimiento/fisiología , Etanol/farmacología , Neuronas/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Metabolismo Energético/fisiología , Histocitoquímica , Plexo Hipogástrico/efectos de los fármacos , Plexo Hipogástrico/enzimología , Plexo Hipogástrico/metabolismo , Masculino , Degeneración Nerviosa/efectos de los fármacos , Neuronas/enzimología , Ratas , Ratas Wistar , Ganglio Cervical Superior/efectos de los fármacos , Ganglio Cervical Superior/enzimología , Ganglio Cervical Superior/metabolismo , Sistema Nervioso Simpático/citología , Sistema Nervioso Simpático/enzimología , Tirosina 3-Monooxigenasa/inmunología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Neurons in the hypogastric (main pelvic) ganglia of 4- and 24-month-old male rats were investigated by enzyme histochemical methods for NADPH-diaphorase (NADPH-d) and acetylcholinesterase (AChE) activities and by immunofluorescence for tyrosine hydroxylase (TH) and neuropeptide Y (NPY) immunoreactivities. Systematic random sampling of standard sized areas of ganglion parenchyma revealed a content (per unit area) of 40.9 +/- 8.41 NADPH-d-positive neurons and 14.42 +/- 6.7 intensely AChE-positive neurons. In the aged rats the staining intensity was unchanged, but reductions in the numbers of cells stained for NADPH-d and AChE were not significantly different. Similar counts of TH- and NPY-immunoreactive neurons revealed values of 23.2 +/- 1.77 and 19.94 +/- 4.9, respectively, suggesting frequent co-localisation. The numbers of TH- and NPY-immunoreactive neurons were found to have decreased with age by 53% and 60%, respectively. Staining of consecutive sections revealed that those neurons which stained positively for NADPH-d did not show immunoreactivity for TH or NPY, and those neurons that were immunoreactive for TH or NPY did not contain intense NADPH-d staining. Occasional NPY-1R neurons were both TH- and NADPH-d-negative. These results suggest that NADPH-d staining is predominantly confined to the parasympathetic neuron population of the hypogastric ganglion and that it is the sympathetic neuron population alone that decreases in number with age.
Asunto(s)
Acetilcolinesterasa/metabolismo , Plexo Hipogástrico/metabolismo , NADPH Deshidrogenasa/metabolismo , Neuronas/metabolismo , Neuropéptido Y/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Envejecimiento/metabolismo , Animales , Técnica del Anticuerpo Fluorescente , Plexo Hipogástrico/enzimología , Plexo Hipogástrico/inmunología , Inmunohistoquímica , Técnicas In Vitro , Masculino , Neuronas/enzimología , Neuropéptido Y/inmunología , Sistema Nervioso Parasimpático/citología , Sistema Nervioso Parasimpático/crecimiento & desarrollo , Ratas , Ratas Wistar , Sistema Nervioso Simpático/citología , Sistema Nervioso Simpático/crecimiento & desarrolloRESUMEN
The biochemical and morphological development of the sympathetic hypogastric ganglion (HG) was examined subsequent to postnatal castration at 10-11 days of age. Previous studies suggested that tyrosine hydroxylase (T-OH) activity, an index of noradrenergic maturation, and choline acetyltransferase (ChAT) activity, a marker for preganglionic terminal formation, were dependent on gonadal hormones during normal ontogeny. In the present studies, morphometric analyses of the HG revealed that the cross-sectional area of the cell soma and nucleus were significantly reduced following postnatal castration at day 10. Conversely, castration produced no change in the number of HG neurons. In addition, postnatal castration prevents the development of postsynaptic T-OH activity to a greater extent than ganglionic protein resulting in a significant loss of T-OH specific activity. In contrast, presynaptic ChAT activity was reduced in parallel with ganglionic protein, thus ChAT specific activity was unchanged. Testosterone replacement therapy, even in groups where treatment was delayed for up to 2 weeks after castration, completely reversed deficits in both T-OH and ChAT activities. These studies suggest that altered development of ganglion protein subsequent to postnatal castration is related to decreases in the size of neurons and not to the loss of neurons. The lack of cell loss also suggest that decreased levels of postsynaptic T-OH activity results from a loss of enzyme activity per cell and the decreased levels of ChAT activity probably represent fewer presynaptic terminals per neuron. In addition, delayed testosterone replacement subsequent to castration was effective in restoring enzyme activities suggesting an 'activational' not 'organizational' role for testosterone after postnatal day 10.
Asunto(s)
Plexo Hipogástrico/crecimiento & desarrollo , Orquiectomía , Animales , Recuento de Células , Colina O-Acetiltransferasa/metabolismo , Plexo Hipogástrico/enzimología , Plexo Hipogástrico/patología , Masculino , Neuronas/enzimología , Neuronas/patología , Ratas , Ratas Endogámicas , Testosterona/administración & dosificación , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
To further evaluate the role of autonomic ganglia in the regulation of pelvic visceral activity, the neural elements in the major pelvic ganglion of the male rat have been studied with histochemixal and electron microscopic techniques. The principal findings are that the ganglion is composed of cholinergic and adrenergic ganglion cells as well as small intensely fluorescent (SIF) cells. Polarity in the ganglion is indicated by clustering of small ganglion cells which stain intensely for acetylcholinesterase (AChE) along the pelvic nerve while larger cells, with weak to moderate AChE activity, collect near small branches of the hypogatrric nerve. Some cholinergic ganglion cells are enclosed by a plexus of adrenergic terminals. SIF cells appear to be in contact with both cholinergic and adrenergic cells, although many of the fluorescent beads around adrenergic neurons may be short dendrites of ganglion cells, rather than processes of SIF cells. Two types of SIF cells may be distingiosjed on the basis of size and morphology of their granulated vesicles. Afferent synapses of the cholinergic type were common on SIF cells of the large granule and small granule type. Portions of SIF cells with large granules occur within the capsule of ganglion cells. Contacts seen here were interpreted as efferent synapses from SIF cells to the dendrites of ganglion cells.
Asunto(s)
Ganglios Autónomos , Plexo Hipogástrico/ultraestructura , Acetilcolinesterasa/análisis , Animales , Catecolaminas/análisis , Gránulos Citoplasmáticos/ultraestructura , Ganglios Autónomos/enzimología , Ganglios Autónomos/ultraestructura , Histocitoquímica , Plexo Hipogástrico/enzimología , Masculino , Microscopía Fluorescente , Neuronas Aferentes/ultraestructura , Neuronas Eferentes/ultraestructura , Sistema Nervioso Parasimpático/ultraestructura , Ratas , Sistema Nervioso Simpático/ultraestructura , Sinapsis/ultraestructuraAsunto(s)
AMP Cíclico/farmacología , Dopamina beta-Hidroxilasa/metabolismo , Norepinefrina/metabolismo , Sistema Nervioso Simpático/metabolismo , Teofilina/farmacología , Animales , Calcio/metabolismo , Cobayas , Plexo Hipogástrico/enzimología , Plexo Hipogástrico/metabolismo , Plexo Hipogástrico/fisiología , Técnicas In Vitro , Masculino , Fenoxibenzamina/farmacología , Conducto Deferente/efectos de los fármacos , Conducto Deferente/enzimología , Conducto Deferente/metabolismoRESUMEN
Dopamine-beta-hydroxylase(DBH), the enzyme that catalyzes the conversion of dopamine to norepinephrine, is localized in the vesicles containing catecholamine in sympathetic nerves. This enzyme is released with norepinephrine when the nerves to the guinea pig vas deferens are stimulated in vitro, and the amount of enzyme discharged increases as the length of stimulation periods increases. The amount of DBH released is proportional to the amount of norepinephrine released, and the ratio of norepinephrine to DBH discharged into the incubation medium is similar to that in the soluble portion of the contents of the synaptic vesicles from the vas deferens. These data are compatible with the release of the neurotransmitter norepinephrine and DBH from symnpathetic nerves by a process of exocytosis.