The Association Between Prenatal Maternal Stress and Adolescent Affective Outcomes is Mediated by Childhood Maltreatment and Adolescent Behavioral Inhibition System Sensitivity.

Prenatal maternal stress is linked to offspring outcomes; however, there is little research on adolescents, behavioral, transdiagnostic outcomes, or the mechanisms through which relations operate. We examined, in N = 268 adolescents (Mage = 15.31 years; SD = 1.063; 57.8% boys) whether prenatal maternal stress is associated with adolescent affective outcomes; whether this association is mediated, serially, by childhood home atmosphere and adolescent behavioral inhibition system (BIS) sensitivity; and whether mediational effects are moderated by adolescent attention-deficit/hyperactivity disorder or maternal internalizing symptomology. Prenatal maternal daily stress and major life events were associated with adolescent outcomes through childhood negative atmosphere/neglect and BIS sensitivity, with no evidence of moderation. Results have implications regarding the effect of prenatal maternal stress on offspring outcomes and regarding corresponding sensitive periods.

Nerve stretch injury induced pain pattern and changes in sensory ganglia in a clinically relevant model of limb-lengthening in rabbits.

We used a model of tibial lengthening in rabbits to study the postoperative pain pattern during limb-lengthening and morphological changes in the dorsal root ganglia (DRG), including alteration of substance P (SP) expression. Four groups of animals (naive; OG: osteotomized only group; SDG/FDG: slow/fast distraction groups, with 1 mm/3 mm lengthening a day, respectively) were used. Signs of increasing postoperative pain were detected until the 10(th) postoperative day in OG/SDG/FDG, then they decreased in OG but remained higher in SDG/FDG until the distraction finished, suggesting that the pain response is based mainly on surgical trauma until the 10(th) day, while the lengthening extended its duration and increased its intensity. The only morphological change observed in the DRGs was the presence of large vacuoles in some large neurons of OG/SDG/FDG. Cell size analysis of the S1 DRGs showed no cell loss in any of the three groups; a significant increase in the number of SP-positive large DRG cells in the OG; and a significant decrease in the number of SP-immunoreactive small DRG neurons in the SDG/FDG. Faster and larger distraction resulted in more severe signs of pain sensation, and further reduced the number of SP-positive small cells, compared to slow distraction.

Neurons of the lateral spinal nucleus in the rat spinal cord - A Golgi study

The neurons of the lateral spinal nucleus in the spinal cord of young adult rats were studied in transverse and longitudinal planes using the Golgi-Kopsch method and electron microscope. The perikarya were mainly polygonal or spindle shaped, and measured 20 to 35 pm in the longest diameter. They formed a dense column in the dorsolateral funiculus underneath the pial surface. The dendrites followed three patterns. Several of them turned laterally and approached the surface of the spinal cord. Another group of dendrites ran longitudinally within the column of the perikarya. A third group of dendrites turned medially or ventromedially and coursed towards the reticulated portion of the gray matter. Medium-sized neurons located at the margin of this latter portion of the spinal cord sent some of their straight dendrites into the dorsolateral funiculus. Thus, the dendrites of these two populations of neurons appeared as rungs of a ladder in longitudinally-cut spinal cord specimens. Only the initial portions of the axons of the LSN neurons could be impregnated. They originated with a regular axon hillock from either the perikaryon or from one of the primary dendrites and became unimpregnated after a 20 to 40 ?m long course, indicating their myelinated character. Preliminary ultrastructural observations revealed that the laterally directed dendrites of the neurons in the lateral spinal nucleus approached the free surface of the spinal cord and ended immediately underneath the pia mater. Large numbers of fine, unmyelinated fibers were found in the dorsolateral funiculus coursing perpendicular to the laterally and medially oriented dendrites (AU)

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Position and size of the axon hillock in various groups of neurons.

The origin of the axon was studied in Golgi-Kopsch impregnated specimens prepared from the spinal cord and brain of adult rats. Five types of neurons were sampled: large ventral horn neurons, neurons in the intermediate zone and ventral horn of the spinal cord, antenna-type neurons in the spinal dorsal horn, neurons in the thalamus, and neurons in the hypothalamus. The axon originated from the perikaryon in 76% of the large ventral horn neurons and in 64% of the neurons in the thalamus. In contrast, the axon emerged from one of the dendrites in 75% of the neurons in the intermediate zone and the ventral horn of the spinal cord and in 68% of the neurons in the hypothalamus. In the case of the antenna-type neurons in the spinal dorsal horn, the axon often originated from one of the dendrites, but never from a dorsally oriented dendrite. The mean distance of the axon hillock of dendritic origin was the longest in the neurons in the intermediate zone and the ventral horn of the spinal cord. The size of the axon hillock was proportional to the size of the perikaryon. The impregnated portion of the axon was longest in the large ventral horn neurons.

Semi-quantitative analysis of somatostatin mRNA distribution in the rat central nervous system using in situ hybridization.

The distribution of somatostatin mRNA in the rat brain has been examined by in situ hybridization using 32P-labelled oligonucleotide probes. Numerous telencephalic and diencephalic areas contained labelled cells with the largest numbers of cells occurring in the anterior olfactory nucleus, olfactory and entorhinal cortices, hippocampus, neocortex, caudate nucleus, accumbens, septum, amygdala and periventricular nucleus. Fewer labelled cells occurred in the mesencephalon and rhombencephalon but groups were seen in the region of the central grey, lateral lemniscus, parabrachial and tegmental nuclei, medial longitudinal fasciculus and nucleus of the solitary tract. This distribution closely matches published maps of the distribution of somatostatin-immunoreactive cell bodies. The intensity of individual cell labelling has also been quantified using image analysis and compared with the intensity of somatostatin immunocytochemical cell staining. In situ hybridization cell labelling varied both within different regions and from region to region. Highest labelling was seen in the periventricular nucleus of the hypothalamus followed by telencephalic regions such as cortex, hippocampus and the medial nucleus of the amygdala. In contrast all brainstem areas had low levels of labelling with the lowest levels of the brain occurring in the dorsolateral tegmental nucleus. Somatostatin immunocytochemistry showed similar variations such that the intensity of cell immunostaining broadly paralleled the intensity of cell in situ hybridization labelling. Thus both peptide and mRNA levels were much lower in brainstem cells than in forebrain, although a close correlation between immunocytochemistry and in situ hybridization was not seen in all brain regions.

Colchicine enhances mRNAs encoding the precursor of calcitonin gene-related peptide in brainstem motoneurons.

Hybridization signals indicating mRNAs encoding the precursor of calcitonin gene-related peptide (CGRP) and CGRP immunoreactivity were detected on parallel sections containing brainstem motor nuclei using in situ hybridization histochemistry and immunohistochemistry. In untreated and saline-injected rats the motoneurons in the hypoglossal, facial motor nuclei and in the ambiguus nucleus showed weak to moderate hybridization signals. In these motoneurons CGRP immunoreactivity was restricted to the Nissl bodies of the perikarya. Twenty-four and 42 hours after intracerebroventricular colchicine injection the intensity of both the hybridization signal and the immunoreaction product increased. The distribution of CGRP immunoreactivity changed from discrete perikaryal localization to diffuse reaction in the perikarya and along the proximal dendritic tree. Motoneurons in the rest of the brainstem motor nuclei (VIth, Vth, IVth and IIIrd) of untreated and saline-injected rats showed neither hybridization signal nor CGRP immunoreactivity. After intracerebroventricular injection of colchicine these motoneurons showed both hybridization signal and CGRP immunoreactivity. In all nuclei the size of motoneurons decreased and their Nissl structure changed to an amorphous basophilic mass following colchicine treatment.

Synapses upon the axon origin of dorsal horn neurons in the rat spinal cord.

Axon terminals synapsing with axon hillocks or origins of Golgi-impregnated and gold-toned neurons in the dorsal horn of the rat were shown in serial electron micrographs. Synapses occurred irrespective of the site (perikaryon or dendrite) and mode (with or without an axon hillock) of the axon origin. The synapsing axon terminals contained 3 populations of vesicles: pleomorphic and flattened synaptic vesicles and a combination of pleomorphic and dense-core vesicles. The membrane thickening in the axon-axon hillock synapses was of the symmetrical type.

Species-specific expression of cholecystokinin messenger RNA in rodent dorsal root ganglia.

The expression of cholecystokinin (CCK) messenger RNA (mRNA) was examined in dorsal root ganglia of rat and guinea pig using in situ hybridization histochemistry and RNA (Northern) blot hybridization with synthetic oligodeoxyribonucleotide (oligomer) probes. In guinea pig, CCK mRNA was detected in small and medium-sized neuronal perikarya comprising approximately 10-15% of the total dorsal root ganglia cell population. In contrast, in neurons of rat dorsal root ganglia, CCK mRNA was not detectable. Northern blot analyses revealed a single CCK mRNA species of expected size (0.8 kb) in guinea pig, but not rat, dorsal root ganglia. A 0.8 kb CCK mRNA was, however, detected in cortex of both rat and guinea pig. These data suggest that CCK is normally not synthesized in neurons of rat dorsal root ganglia and that there are species differences in CCK gene expression in mammalian sensory ganglia.

Termination patterns of calcitonin gene-related peptide-immunoreactive nerve fibers in the dorsal horn of the human spinal cord.

CGRP-immunoreactive varicose nerve fibers displayed three kinds of termination patterns in the cervical, thoracic and lumbar segments of the human spinal cord. Bundles of immunoreactive fibers formed a loose network in lamina I. A homogenous band of immunoreactive fibers filled lamina II. Multiple bundles of CGRP-positive fibers coursed through the superficial laminae towards deep portions of the grey matter. In the lumbar segments, in contrast to the cervical and thoracic segments, the bundles could be followed deep into the dorsal funiculus. Bundles of varicose immunoreactive fibers were seen to twine around the dendrites of neurons located in lamina I, in the dorsal funiculus of the lumbar segments and deep in the dorsal horn (laminae III-V). The corresponding types of large and medium-sized neurons were found in silver impregnated adjacent spinal cord sections. It is suggested that neurons in the above locations preferentially receive multiple contacts from CGRP-containing nerve fibers along their extensive dendritic arborizations (CGRP-target neurons).

Synaptic ultrastructure of functionally and morphologically characterized neurons of the superficial spinal dorsal horn of cat.

Recordings of neuronal unitary discharges evoked by primary afferent input were made in the superficial part of the spinal cord's dorsal horn, the marginal zone and substantia gelatinosa (also known as laminae I and II), using fine micropipette electrodes filled with HRP. After physiological characterization with respect to primary afferent input, HRP was injected intracellularly iontophoretically into the recorded neuron. Following histochemical processing, the neurons so delineated were studied at the light and electron microscopic levels. No clear relationship between function and either general cellular configuration or synaptic ultrastructure appeared in these analyses, although the concentration of dendritic distribution could be related to the nature of primary afferent excitation. Nocireceptive cells had dendrites mostly branching and ending in lamina I and IIo, while the dendrites of innocuous mechanoreceptive cells arborized principally in lamina II and III. Glomerular synaptic complexes (large, complex arrays of axonic and dendritic profiles with synaptic interconnections) were found to contact a few neurons of both the nocireceptive and mechanoreceptive classes. All neurons received large numbers of simple axonic contacts (small axonic boutons with only 1 or 2 synaptic contacts with a single postsynaptic profile). A degree of specificity in the presynaptic articulations appeared to be reflected by the observations that (1) nocireceptive neurons were never found to receive synaptic contacts from boutons which resembled the known ultrastructure of peripheral innocuous mechanoreceptors, and (2) mechanoreceptive neurons were never seen to receive synaptic contacts from boutons which resembled the known ultrastructure of primary afferent nocireceptors. The axons of the labeled neurons of both nocireceptive and mechanoreceptive classes terminated in simple axonic synapses. All classes of neurons participated in dendrodendritic contacts; however, only some mechanoreceptive neurons had dendrites containing vesicles that were presynaptic to other profiles. No nocireceptive neurons, regardless of gross configuration, were found to have vesicles in their dendrites, but 3 nocireceptive neurons received synapses from presynaptic dendritic profiles.

Distribution of neurons expressing calcitonin gene-related peptide mRNAs in the brain stem, spinal cord and dorsal root ganglia of rat and guinea-pig.

In situ hybridization histochemistry was used to localize calcitonin gene-related peptide mRNAs in spinal cord, brain stem and dorsal root ganglion neurons of the rat and guinea-pig. A 32P-labeled 23-base-long (23mer) oligodeoxyribonucleotide (oligomer) complementary to calcitonin gene-related peptide mRNA sequences encoding residues 23-30 of calcitonin gene-related peptide was used primarily as a probe (CGRP I probe). A 32mer complementary to mRNA sequences for residues 10-20 of calcitonin gene-related peptide (CGRP II probe) was also used as a positive control for specificity of the 23mer for calcitonin gene-related peptide mRNA. In both the guinea-pig and rat calcitonin gene-related peptide mRNA was localized specifically to neurons of the dorsal root ganglion, to spinal motoneurons and to motoneurons of the hypoglossal, facial and accessory facial motor nuclei. Differences in the distribution of calcitonin gene-related peptide mRNA between the rat and guinea-pig included a higher proportion of rat dorsal root ganglion neurons containing calcitonin gene-related peptide mRNA and the localization of calcitonin gene-related peptide mRNA to motoneurons of the ambiguus motor nucleus, parabrachial and peripeduncular nucleus of the rat but not the guinea-pig. In the guinea-pig, in contrast, calcitonin gene-related peptide mRNA was localized also to motoneurons of the abducens, trigeminal, trochlear and oculomotor nerves. The neuronal groups in the intact rat found here to contain calcitonin gene-related mRNA have also been shown previously to contain calcitonin gene-related peptide immunoreactivity in colchicine-treated rats. Colchicine-treated rats, however, have been found to contain additional groups of calcitonin gene-related peptide immunoreactive neurons which, in the intact rats used in the present study, showed no detectable hybridization with the calcitonin gene-related peptide probe.

In situ hybridization of peptide mRNAs on vibratome sections.

In situ hybridization procedures that have been used successfully for the localization of somatostatin and cholecystokinin mRNAs in neurons on cryostat sections of rat brain, were tested for applicability to vibratome sections of rat and guinea pig brain. Somatostatin and cholecystokinin mRNAs were localized to neurons in 30 microns thick vibratome sections of brain from both species by use of 32P labelled oligodeoxyribonucleotide (oligomer) probes. Somatostatin mRNAs was localized to neurons in the periventricular region of the preoptic area of rat, and guinea pig brain. Cholecystokinin mRNAs were localized to neurons of rat hippocampus. Hybridization signal, background and resolution achieved with vibratome sections were comparable to those obtained with the more commonly used cryostate sections.

In situ hybridization using 32P labelled oligodeoxyribonucleotides for the cellular localisation of mRNA in neuronal and endocrine tissue. An analysis of procedural variables.

Methodological variables for in situ hybridization using 32P labelled oligodeoxyribonucleotides (oligomers) have been examined. Four different oligomers directed against proglucagon messenger RNA (mRNA) and two different oligomers against prosomatostatin mRNA have been used. Specific hybridization was obtained in adult rat brain, stomach and pancreas and in neonatal rat ileum. Tissue was perfusion fixed with 4% paraformaldehyde 0.2% glutaraldehyde and hybridization was carried out in 50% formamide for 72 h at 42 degrees C. Using hybridization conditions of lower stringency (33% formamide) labelling was also obtained in guinea pig tissue. Other variables which affected hybridization signal intensity were the inclusion of a prehybridization dehydration stage, the probe concentration, the inclusion of ammonium acetate in the posthybridization dehydrating ethanols and in the autoradiographic emulsion, and the exposure time. The localisation of proglucagon mRNA in rat pancreas using a 20mer was used as a model tissue for testing these methodological variables and the results were found generally also to apply to the other probes and tissues tested. The methods described provide single cell resolution and show that 32P labelled oligomers may be used to localise neuropeptide and endocrine mRNAs in different types of tissue and in different mammalian species.

Altered distribution of dorsal root fibers in the rat following neonatal capsaicin treatment.

Distribution of primary afferent fibers was studied in intact and neonatally capsaicin treated rats by the application of horseradish peroxidase to the central branch of the transected lumbar dorsal roots. Coarse primary afferent fibers entered the spinal cord through the larger medial portion of the rootlet and arborized in the deeper part of the dorsal horn (laminae III and IV). Fine fibers reached the spinal cord through the smaller lateral portion of the rootlet and arborized in the superficial portion of the dorsal horn (lamina I and outer portion of lamina II). The technique used was inadequate to stain fine, unmyelinated primary afferent fibers terminating in the larger inner portion of lamina II. After neonatal capsaicin treatment (50 mg/kg) the flame-shaped arborizations of thick primary afferent fibers terminating in intact rat in laminae III and IV spread dorsally and occupied the inner portion of lamina II in the larger lateral sector of the dorsal horn. Medially the dense arborization of a different type of thick primary afferent fibers sprouted up to the white-gray border. The border between the lateral and medial sector was sharp and only slightly varied in localization from experiment to experiment. The sprouting fibers established complicated synaptic contacts with dendrites and axon terminals. The rearrangement of primary afferent fibers after neonatal capsaicin treatment confirmed earlier results and revealed a mediolateral difference in the fiber organization of the dorsal horn indicating differences in the projection from hairy vs non-hairy skin areas.

Quantitative analysis of dendritic protrusions in the medial preoptic area during postnatal development.

Dendritic architecture and distribution of dendritic protrusions were studied on Golgi-impregnated neurons in the medial preoptic area (MPOA) of infant rats (7 and 20 days old), of animals at puberty (34 days old) and of postpubertal rats (90 days old) using computerized image analysis. The protrusions showed a peak distribution on the proximal portion of the dendritic tree in infant rats. At puberty and in postpubertal animals protrusions disappeared almost completely along the most proximal portion of the dendritic tree. The data suggest that differentiation of certain MPOA neurons is still in progress at puberty.

Axonal regeneration following retrochiasmatic deafferentation in young and adult rats.

Regeneration of nerve fibres after hypothalamic knife cuts was studied by the anterograde transport of horseradish peroxidase [HRP] in female rats of various ages. Retrochiasmatic frontal cuts were made in 2, 5, 7 and 11-day-old and in adult rats. Four, 6, 7 and 12 months later HRP was injected rostral to the cut-line in the suprachiasmatic area. HRP-stained nerve fibres ran rostro-caudally from the injection site through the cut-line in animals operated upon at 2, 5 and 7 days of age. In contrast to the former group, animals operated on the 11th day of life as well as in adult rats no HRP-stained nerve fibres could be seen passing through the cut-line which was marked by scar formation. In one animal operated in adulthood a bundle of nerve fibres noticed 7 months after the surgery turned medially at the caudal end of the cut-line and spread over the frontally deafferented area. The character of these newly formed fibres was different: part of them showed a varicose appearance, the others exhibited even contours. The present findings indicate that the deafferented [or isolated] hypothalamus remains neuronally isolated from the environment if the operation is carried out later than the end of the first week of life. Operations made during the first postnatal week do not leave permanent traits in the brain.

Approximation of missing sections in computer reconstruction of serial EM pictures.

Replacing missing contours or completing a series of contours of biological structures has been investigated. The paper reports on a method for approximating lateral surfaces between adjacent contours and generating new artificial outlines by slicing the interpolated surface parallel with the original sections. The research method was developed mainly due to the need to fill in damaged or missing ultrathin sections in longer series, since their absence may impede the three-dimensional visualization of selected components. The new program attached to the shape reconstruction program system existing at Second Department of Anatomy, Semmelweis University Medical School, Budapest, Hungary also permits new contours to be generated into the models of single or branching objects. Besides replacing missing contours, the program makes the reconstructed model more precise.

Dendritic arborization and axon trajectory of neurons in the hypothalamic arcuate nucleus of the rat--updated.

Neurons in the hypothalamic arcuate nucleus (arcuate neurons) were traced on Golgi-impregnated sections. Dendrites of arcuate neurons showed characteristic orientation patterns. Dendrites along the lateral side follow the convex border of the nucleus by running parallel to the tanycyte processes. Neurons located in the ventrolateral portion of the nucleus have dendrites running parallel to the basal surface of the hypothalamus. Fine, beaded axons of arcuate neurons project mostly ventrally, and less frequently dorsally and dorsolaterally. Ventrally projecting axons converge towards the tuberoinfundibular sulcus which emerges into the ventral portion of the arcuate nucleus from below.

Lamellar arrangement of neuronal somata in the dorsal root ganglion of the cat.

The retrograde transport of horseradish peroxidase (HRP) was used to study the distribution of perikarya in the dorsal root ganglia (DRGs). Injections of HRP subcutaneously into a small area of the foreleg, flank, perineum, the central pad of the forepaw, muscles of the foreleg, the wall of the urinary bladder, and mucosa of the rectum resulted in many retrogradely labeled perikarya in one DRG. Labeled perikarya were distributed in the ganglia proximally to distal elongated slabs or columns, especially in cases of subcutaneous injections. A similar slab, or columnar distribution, of HRP-labeled perikarya was noticed when the tracer was injected into the spinal cord preceded by the transection of all dorsal root filaments but one. Perikarya located along the lateral border of the ganglion were labeled through rostral filaments, and perikarya distributed along the medial border were labeled through caudal filaments. A segmental somatotopic map has been conceived for the DRG as an intermediate territory between the periphery and the spinal cord.