Biomedical subjects

J Rodrigo

Publications and source records attributed to J Rodrigo.

At least 91 records · Page 5Linked to original sources

PubMed1991

Lasting loss in substance P following administration of substance P antiserum to newborn rats. An immunohistochemical study.

Substance P (SP) antiserum (500 micrograms protein) was administered to rats on the second day of life and the animals were sacrificed 3 months later. This treatment produced a loss in SP immunoreactive fibers in the dorsal horn of the spinal cord, in the substantia nigra and in the periaqueductal gray matter, when compared to control animals receiving a neonatal treatment of non-specific immunoglobulins. In the dorsal horn, the observed depletion was greater in the superficial layers, lamina I and lamina IIo. Immunoreactivity for Met-enkephalin was apparently unchanged by SP antiserum. Results of this study provide cytochemical evidence for a specific and lasting deleterious effect of SP antiserum on different SP-containing neuronal systems.

Animals↗

PubMed1991

Subcellular localization of nerve growth factor receptors in identified cells of the rat nucleus basalis magnocellularis: an immunocytochemical study.

The subcellular location of nerve growth factor receptor in the ventromedial portion of rat globus pallidus was investigated with affinity-purified monoclonal 192-IgG following the unlabelled antibody peroxidase-antiperoxidase immunocytochemical procedure. At the light microscopic level, punctate immunoreaction product was observed in the perinuclear region and in the plasma membrane of large, probably cholinergic neurons. Examination in the electron microscope of these neurons confirmed that nerve growth factor receptor-stained cells were basal forebrain cholinergic neurons. Within these cells, immunostaining occurred in the Golgi apparatus, in multivesicular bodies and, occasionally, in rough endoplasmic reticulum cisternae and the nuclear envelope. Moreover, patches of immunoreactivity were observed associated with the outer surface of the plasma membrane of the soma and their proximal dendrites and also with the plasma membrane of distal dendrites showing scarcity of synaptic input. Positive immunostaining was never observed in synaptic clefts, but filled the space between the plasma membranes of immunoreactive neurons and those of thin glial processes in their vicinity. The location of membrane nerve growth factor receptor in close apposition to membranes of neighbouring astrocytes rather than near synaptic complexes, suggests that glial cells may be a physiological source of nerve growth factor.

Animals↗

PubMed1990

Distribution of small-diameter primary afferents containing oligosaccharide residues recognized by monoclonal antibody LA4 in the dorsal horn of the cat.

Small-diameter primary afferents expressing oligosaccharide residues recognized by the monoclonal antibody LA4 constitute a newly described primary afferent population in the cat. LA4-immunoreactive primary afferents are found mainly in lamina II (LII) at all levels of the cat spinal cord. However, within LII immunoreactive fibers are most concentrated in outer LII and practically absent from the inner third of the lamina. In addition at sacral levels, a lateral bundle of immunoreactive fibers enters laminae V-VII. The distribution pattern and the type of oligosaccharide expressed by LA4-immunoreactive fibers suggest that they may be homologous to primary afferents shown in the rat to contain fluoride-resistant acid phosphatase activity. However, in the rat spinal cord the whole of inner LII is the main projection area of LA4-immunoreactive fibers (Alvarez et al., J. Neurocytol., 18 (1989) (611-629). This difference in the location of primary afferents within LII may reflect a species difference in the physiology of LII inner.

Afferent Pathways↗

PubMed1990

[Medical counseling, nursing counseling, and nicotine chewing gum for smoking cessation in primary care].

The 2-month results of a study designed to compare the effectiveness of three methods to encourage giving up smoking in primary health care are reported: individualized medical counseling (minimal intervention), counseling plus follow-up option by the nurse, and medical counseling plus nicotine chewing gum. Overall 425 smokers between 15 and 65 years of age were included in the study. In 349 of them (82%), short term follow-up was carried out by phone interview. The proportion who declared to have given up smoking, after adjustment for the estimated validity of the phone report of smoking status, was 10, 9%, 10.8% and 11.1%, respectively, without significant differences between the three groups. In the logistic regression analysis, only the existence of concomitant disease and the anticipated difficulty in giving up smoking appeared as predictive variables of abstention. The implications of the results for the strategies to control smoking are discussed.

Adolescent↗

PubMed1990

Neuropeptide Y (NPY)-containing nerves in mammalian ureter.

The distribution of neuropeptide Y in the ureter of the rat, rabbit, and man has been determined by radioimmunoassay and chromatographic analysis of the tissue extract. The localization of neuropeptide Y-immunoreactivity has been identified by immunocytochemistry. A regional distribution of neuropeptide Y was found; highest concentrations being present in the ureterovesical junction. Throughout the ureter, neuropeptide Y-immunoreactive nerve fibers were identified to surround the blood vessels and a few plexuses of neuropeptide Y-containing nerves were present within the muscle layers. Neuropeptide Y was not present within ganglion cells. Treatment of rats with 6-hydroxydopamine resulted in a significant reduction of neuropeptide Y concentrations in the upper, middle, and lower thirds of the ureter. This depletion in extractable neuropeptide Y was associated with morphologic changes typical of axonal degeneration of the neuropeptide Y-containing nerve fibers.

Animals↗

PubMed1990

Immunocytochemical localization of cholinergic terminals in the region of the nucleus basalis magnocellularis of the rat: a correlated light and electron microscopic study.

The cholinergic circuitry in the nucleus basalis magnocellularis of the rat was investigated in a correlated light and electron microscopic study by using monoclonal antibodies against the acetylcholine-synthesizing enzyme, choline acetyltransferase, following the unlabelled antibody peroxidase-antiperoxidase immunocytochemical procedure. After the immunocytochemical approach, large cholinergic cells and a few immunoreactive fibres exhibiting a varicose appearance, were detected by light microscopy in portions of the nucleus basalis magnocellularis located within the anatomical limits of the globus pallidus, mostly in its ventromedial part. Cholinergic neurons and fibre-like structures were also found within the substantia innominata on the edge of globus pallidus. The same material studied by light microscopy was analysed with the electron microscope. At the ultrastructural level, the immunopositive neurons showed the same cytological characteristics and pattern of synaptic input as cholinergic basal forebrain cells. Additionally, scarce immunoreactive preterminal axons and terminal boutons were detected in the region. The immunoreactive terminals were scattered or formed occasional clusters and appeared as heavily immunostained vesicle-filled boutons making exclusively axodendritic synaptic contacts principally with immunonegative distal dendrites. Both symmetric and asymmetric synaptic contacts established between these structures were detected, although the symmetric contacts were the more numerous. The surface of postsynaptic immunonegative dendrites in asymmetric synaptic contact with immunoreactive terminals was generally covered by terminals that lacked detectable immunoreactivity. In contrast, those in symmetric synaptic contact with labelled terminals showed much sparser input from immunonegative terminals, suggesting that they may belong to interneurons. Very rarely, cholinergic terminals were detected in asymmetric synaptic contact with dendrites which also contained positive immunoreaction product. Asymmetric contacts were frequently characterized by the presence of subjunctional dense bodies. The detection of cholinergic terminals in the region of the nucleus basalis magnocellularis of the rat indicates that this region not only contains cholinergic projecting neurons, but receives a cholinergic input itself. Results of this study provide evidence of the existence of a cholinergic transmission in the basal forebrain of the rat, and also that acetylcholine might play a role in the regulation of the extrinsic cortical cholinergic innervation. The possible sources of this innervation are discussed.

Animals↗

PubMed1989

Light and electron microscopic study of galanin-immunoreactive nerve fibers in the rat posterior thalamus.

Light and electron microscopic immunocytochemistry was used to study certain cell groups in the posteromedial thalamus which contain galanin-immunoreactive (GAL-IR) fibers. The nuclei subparafascicularis pars parvicellularis (SPFpc) and parafascicularis (PF) contain a dense network of GAL-IR fibers which form basketlike structures around unstained cells. The periventricular area also contains numerous GAL-IR fibers and these also occasionally form basketlike structures. The GAL-IR terminal fields continue caudally in the mesodiencephalic junction and merge with other GAL-IR fibers in the dorsal aspects of the substantia nigra and around the dorsolateral tip of the medial lemniscus. Ultrastructural analysis of the GAL-IR basketlike structures revealed that GAL-IR terminals make numerous synapses with the cell bodies and proximal dendrites of SPFpc neurones. These results suggest that the activity of cells in the SPFpc and PF nuclei may be strongly influenced by galanin-containing nerve fibers probably originating in the spinal cord.

Animals↗

PubMed1989

Cholinergic somata and terminals in the rat substantia nigra: an immunocytochemical study with optical and electron microscopic techniques.

The topographical distribution, histochemical characteristics, and anatomical relationships of the cellular elements containing choline acetyltransferase (ChAT) immunoreactivity, demonstrated with specific monoclonal antibodies to ChAT following the unlabelled antibody peroxidase-antiperoxidase (PAP) procedure at the optical and electron microscopic levels, were investigated in the rat substantia nigra (SN). Scarce, large (20-30 microns in maximum soma extent) cholinergic cell bodies and processes were found within the boundaries of the SN, in the borders of the pars compacta and pars reticulata, principally at caudal levels. Occasionally, cholinergic neurons were also found at intermediate levels of the SN, in the borders of the pars reticulata and pars lateralis. Cytologically, these large cells resembled ChAT-positive neurons localized in other areas of the central nervous system (CNS) of the rat--for example, the pontomesencephalotegmental (PMT) cholinergic complex (Ch5-Ch6) and the nucleus basalis of Meynert (nbM) (Ch4). Histochemically, ChAT-positive cells in the SN were characterized by their ability to utilize the reduced cofactor nicotinamide adenine dinucleotide phosphate (NADPH). Identified ChAT-positive neurons in the light microscope were subsequently studied in the electron microscope. All cholinergic neurons in the SN share essentially the same ultrastructural characteristics. The copious cytoplasm was rich in organelles with large lipofuscin granules. The synaptic input onto cell bodies and their dendrites was studied in serial sections. Synaptic contacts onto the perikarya and proximal dendrites were sparse and of asymmetric type. Both symmetric and asymmetric synaptic specializations onto ChAT-positive distal dendrites were detected. Asymmetric synaptic contacts onto cell bodies and dendrites were often defined by the presence of subjunctional dense bodies associated with the postsynaptic membrane. The pattern of the synaptic input to these cells differs strikingly from that onto unlabelled neighboring neurons. The perikarya and dendrites of the latter were characteristically covered with synaptic boutons. Scarce immunoreactive terminals in asymmetric synaptic contact with unlabelled dendritic profiles were also detected in portions of SN compacta with no ChAT-positive cells. Extranigrally located ChAT-positive cells of the PMT cholinergic complex were also examined in the electron microscope for comparison purposes. These cells exhibited, on the basis of their morphology and synaptic input pattern, very similar characteristics to those shown by SN cholinergic neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

Acetylcholinesterase↗

PubMed1989

Electron microscopic localization of cholinergic terminals in the rat substantia nigra: an immunocytochemical study.

The presence of cholinergic terminals in the substantia nigra (SN) of the rat was investigated under the electron microscope using a monoclonal antibody against choline acetyltransferase (ChAT), the acetylcholine (ACh)-synthesizing enzyme, following the unlabelled antibody peroxidase-antiperoxidase (PAP) procedure. ChAT-immunoreactive terminals were found making synaptic contacts with unlabelled dendrites in the SN pars compacta (SNC). Synaptic contacts established between cholinergic boutons and immunonegative dendrites were observed in serial sections to be of asymmetric type. The unlabelled postsynaptic dendrites to immunoreactive terminals displayed similar morphological aspects to typical dopamine-containing dendrites of the SN. Results of this study provide fine ultrastructural neurochemical support for the existence of a cholinergic innervation of the rat SNC and are consistent with the reported excitatory action of ACh on SNC dopaminergic neurons.

Animals↗

PubMed1989

Morphology and distribution of primary afferent fibres expressing alpha-galactose extended oligosaccharides in the spinal cord and brainstem of the rat. Light microscopy.

The light microscopic morphology and distribution of non-substance P-containing small primary afferent fibres were studied. These fibres were labelled using LD2 and LA4 monoclonal antibodies which recognize alpha-galactose extended oligosaccharides expressed by primary afferent neurons. The LD2 and LA4 antibodies immunostained small primary afferent fibres ending mainly in lamina II of the spinal cord dorsal horn and trigeminal subnucleus caudalis of the rat. The lamination pattern of both types of primary afferents was assessed using an image analysis system. The highest density of LD2-immunoreactive fibres was located in a patchy band located in lamina II outer, while LA4-immunoreactive fibres were distributed mainly through lamina II inner. In lateral regions of cervical and lumbar dorsal horn the LA4-immunoreactive band is broader and comprises almost all lamina II. In contrast to substance P-containing primary afferents, a low density of LD2- or LA4-immunoreactive fibres was found in lamina I, and no terminal fields were found in lamina V or lamina X of the spinal cord or in levels of the trigeminal system outside the subnucleus caudalis. Both antibodies also labelled the parent fibres in the white matter fasciles. LD2-immunoreactive fibres were located in the dorsal roots, medial regions of the Lissauer tract, dorsal columns of the spinal cord, outer regions of the spinal trigeminal tract and dorsal to the cuneatus and gracilis nuclei. In contrast, LA4-immunoreactive fibres were restricted to the dorsal roots, medial and lateral regions of the Lissauer tract and the outer regions of the trigeminal tract. Immunostained fibres in the rootlets of the X and IX nerves and immunoreactive terminal arborizations in various subnuclei of the nucleus tractus solitarius were seen using both antibodies. These results show that subpopulations of small primary afferents stained by LD2 and LA4 antibodies have distinct patterns of central distribution and are consistent with a subdivision of small primary afferents into peptide- and non-peptide-containing groups.

Animals↗

PubMed1989

Ultrastructure of primary afferent fibres and terminals expressing alpha-galactose extended oligosaccharides in the spinal cord and brainstem of the rat.

The ultrastructural characteristics of primary afferent fibres, which express alpha-galactose extended oligosaccharides recognized by LD2 and LA4 monoclonal antibodies, and the subcellular localization of these oligosaccharides were studied. LD2 and LA4 antibodies both label intensely the plasma membrane of primary afferent fibres, and with LD2 antibody all immunoreactive profiles also possessed strong intracellular staining. In contrast, intracellular staining with LA4 antibody was observed in only a subpopulation of stained profiles. LD2-immunoreactive fibres were detected in trigeminal and Lissauer tracts and in lamina I (LI) and lamina II (LII), and appeared as a mixture of unmyelinated and myelinated fibres. The highest density of LD2-immunoreactive synaptic boutons was found in lamina II outer (LIIo). Many of the terminals were simple dome-shaped terminals, making single asymmetric synapses over small and medium-sized dendritic shafts and dendritic spines. All LA4-immunoreactive fibres were unmyelinated. In addition, some small scalloped central-glomerular terminals contacting two or three dendrites were found. LA4-immunoreactive fibres were found more frequently than terminals and appeared most heavily immunostained in trigeminal and Lissauer tracts. In the neuropil of LI and LII, LA4 profiles were generally very weakly immunostained, although a small sample of immunostained synaptic boutons was detected. All LA4-immunoreactive terminals were found in lamina II inner (LIIi) and made simple asymmetric axodendritic synapses. In addition to axons and terminals, some dendrites exhibited LD2 immunoreactivity and this was most intense in the region of synaptic vesicles. In addition to neurons, some endothelial cells were immunostained with LD2 antibody and astrocytes were immunostained with LA4 antibody.

Animals↗

PubMed1989

Distribution and density of neuropeptide Y-immunoreactive nerve fibres and cells in the horse urinary bladder.

The distribution and density of neuropeptide Y (NPY)-immunoreactive nerve fibres and cells were determined in the urinary bladder of the horse by using the peroxidase-antiperoxidase (PAP) immunohistochemical method. Numerous undulating NPY-immunoreactive nerve fibres were found throughout the vesical wall, sometimes forming nerve bundles which ramified repeatedly as they coursed through the connective tissue septa to give rise to smaller bundles or single fibres which projected into the muscle fascicles forming muscular nerve plexuses, mainly in the bladder base. In the submucosa of this region, NPY-immunoreactive fibres formed a rather dense subepithelial plexus. Numerous NPY-immunoreactive nerve fibres supplied blood vessels and were widely distributed on the vascular adventitia constituting rich perivascular nerve plexuses. In addition, intramural ganglia containing NPY-immunoreactive nerve cell bodies and fibres were identified at the uretero-vesical junction. These results suggest that the equine urinary bladder possesses a rich NPY-peptidergic innervation which shows regional variations in the density of the muscular and subepithelial plexuses, the bladder base being the most richly innervated region. At least some of these NPY-immunoreactive nerve fibres have an intrinsic origin in ganglion cells within the vesical wall.

Animals↗

PubMed1989

Localization of C-PON immunoreactivity in the rat main olfactory bulb. Demonstration that the population of neurons containing endogenous C-PON display NADPH-diaphorase activity.

The presence of the neuropeptide C-terminal flanking peptide of neuropeptide-Y, C-PON, has been investigated in the main olfactory bulb of the rat using conventional fluorescence and peroxidase-antiperoxidase immunocytochemical techniques. The distribution of immunoreactive structures to C-PON was examined in both horizontal and coronal sections. Endogenous C-PON was localized within two types of short-axon cells including (1) superficial short-axon cells in the glomerular layer and (2) deep short-axon cells lying in the deepest portion of the granule cell layer and in the adjacent white matter. In addition, varicose immunoreactive processes were detected in all layers, although they were more numerous in the deepest portion of the granule cell layer. Immunoreactive cell bodies and processes were also observed in the nucleus olfactorius anterior and in the intrabulbar portion of the anterior commissure. Nevertheless, immunoreactive structures were not localized in the lateral olfactory tract. The indirect immunofluorescence technique to detect endogenous C-PON in combination with the enzyme histochemical demonstration of NADPH-diaphorase activity, in single sections, showed that the NADPH-diaphorase procedure is a reliable marker for these C-PON positive cells. Also, indirectly, that, in the rat main olfactory bulb, C-PON and neuropeptide-Y are contained in the same cell types. Many glomeruli were stained following the NADPH-diaphorase procedure, but they were not C-PON immunoreactives. Results of this study provide evidence suggesting that C-PON may influence polysynaptically the function of mitral cells and, therefore, the olfactory bulb output.

Animals↗

PubMed1988

C-PON containing neurons in the rat striatum are also positive for NADPH-diaphorase activity. A light microscopic study.

The indirect immunofluorescence technique to detect endogenous C-flanking peptide of neuropeptide Y (NPY), C-PON, in combination with NADPH-diaphorase (NADPH-d) histochemistry, were applied to the same sections to establish whether C-PON containing cell bodies in the rat striatum can be labelled by their content of NADPH-diaphorase activity. NADPH-diaphorase activity proved to be a reliable marker for these positive C-PON neurons. Our results suggest that, in the rat striatum, C-PON, SOM and NPY co-exist in the same cells.

Animals↗

PubMed1988

Presence of calcitonin gene-related peptide (CGRP) and substance P (SP) immunoreactivity in intraepidermal free nerve endings of cat skin.

Immunocytochemistry against neuropeptides contained within primary afferent neurons was used to study the morphology and distribution of intraepidermal free nerve endings in cat facial skin. Calcitonin gene-related peptide (CGRP) and substance P (SP) immunoreactivity was found in similar intraepidermal nerve endings of cat glabrous and hairy skin epithelia. The greatest density of immunoreactive intraepidermal nerve endings was located in the nose epidermis. Small limited areas with immunoreactive intraepidermal nerve endings were also found in facial hairy skin.

Afferent Pathways↗

PubMed1988

Immunocytochemical analysis of calcitonin gene-related peptide and vasoactive intestinal polypeptide in Merkel cells and cutaneous free nerve endings of cats.

Calcitonin gene-related peptide (CGRP)- and vasoactive intestinal polypeptide (VIP)-immunoreactivity were observed to coexist in Merkel cells of cats. No differences in peptide content were found between Merkel cells located in epithelia of the hard palate, in hairy and glabrous skin of the upper lip, and in vibrissae follicles. CGRP- and VIP-immunoreactive nerve fibres were also found near CGRP/VIP-immunoreactive Merkel cells. In the vibrissae follicles some CGRP- and VIP-immunoreactive nerve terminals end abutting on the glassy membrane. Other CGRP-immunoreactive nerve fibres penetrate the epithelium of the skin and end within it. Electron microscopy of vibrissae follicles revealed that Merkel cell neurites are not immunostained and that immunostained nerve fibres form unmyelinated bundles before ending freely. Thus, CGRP- and VIP-immunoreactive nerve fibres in cat skin do not end as Merkel cell neurites but as different kinds of free nerve endings.

Animals↗

PubMed1988

Distribution of enkephalin-immunoreactive nerve fibres and terminals in the region of the nucleus basalis magnocellularis of the rat: a light and electron microscopic study.

This investigation was carried out on the distribution of enkephalin-containing nerve fibres and terminals in the region of the nucleus basalis magnocellularis (NBM) of the rat. At the light microscope (LM) level, enkephalin-immunoreactive sites and endogenous choline acetyltransferase (ChAT) were demonstrated by employing the two-colour immunoperoxidase staining technique, using highly specific monoclonal antibodies against enkephalin and ChAT. A pharmacohistochemical procedure to reveal acetylcholinesterase (AChE)-synthesizing neurons combined with the peroxidase-antiperoxidase (PAP) immunocytochemical technique to detect endogenous enkephalins, provided ultrastructural data on the relationships of neuronal elements containing AChE and enkephalins in the region of the NBM. At the LM level, cholinergic neurons of the NBM were surrounded by a dense network of enkephalin-immunoreactive nerve fibres. Electron microscopic (EM) observations of histochemically characterized structures, that were first identified in the LM, revealed that intensely AChE-stained structures in the region of the NBM received sparse synaptic inputs from enkephalin immunoreactive terminals. Synaptic inputs of immunoreactive terminals onto intensely AChE-stained neuron cell bodies were not detected. Synaptic contacts onto proximal AChE-positive dendrites were sparse, but the density increased on more distal regions of the dendrites. All immunoreactive boutons studied established symmetrical synaptic contacts with AChE-positive post-synaptic structures. The pattern of the synaptic input to these cells differs strikingly from that onto typical globus pallidus neurons. The perikarya and dendrites of the latter neurons were characteristically ensheathed in immunoreactive synaptic boutons. Results are consistent with the view that enkephalin-like substances in the rat might be synaptic transmitters or neuromodulators in the area of the NBM and that cholinergic neurons of the NBM (Ch4) are integrated into the circuitry of the basal ganglia. Enkephalins may play an important role regulating the extrinsic cholinergic innervation of the neocortex.

Acetylcholinesterase↗

PubMed1986

Calcitonin gene-related peptide-immunoreactive nerves in the tongue, epiglottis and pharynx of the rat: occurrence, distribution and origin.

The occurrence, distribution and nature of calcitonin gene-related peptide (CGRP) in the tongue, epiglottis and pharynx of the rat was investigated by immunocytochemistry and radioimmunoassay. Numerous CGRP-containing nerves were found to innervate and terminate freely within the epithelium of the tongue, epiglottis and pharynx. Immunoreactive fibres were also found in the muscle layer and around blood vessels in the tongue, and in motor end plates in the muscle of the epiglottis and pharynx. Section of the trigeminal nerve induced a marked reduction in the number of immunoreactive nerves in the anterior portion of the tongue, whereas glossopharyngeal denervation results in a depletion of CGRP immunoreactivity in the posterior portion of the tongue. Immunoreactive nerves of the epiglottis and pharynx were depleted only after superior laryngeal nerve section. A subpopulation of labelled primary sensory neurones were observed in trigeminal and glossopharyngeal ganglia following injection of True blue retrograde tracer in the tongue. Most of the labelled cells were also immunoreactive for CGRP. Following systemic treatment with capsaicin, a loss of intra- and subepithelial CGRP-immunoreactive nerves was observed in all investigated tissues, while immunoreactive motor end plates remained unchanged.

Animals↗