neuropeptide-y and true-blue

The present paper reviews recent studies in monkey and man adding further to understanding of the role of perivascular peptides in the pathophysiology of subarachnoid haemorrhage. 1. The perivascular fibers, sympathetic fibers (storing noradrenaline, neuropeptide Y), parasympathetic fibers (storing acetylcholine, vasoactive intestinal peptide, peptide histidine methionine and neuropeptide Y) and sensory fibers (storing tachykinins, calcitonin gene-related peptide) were traced using True Blue in monkey. 2. Tracing studies of the monkey middle-cerebral artery (MCA) innervation confirmed earlier studies in rats and cats, with superior cervical and trigeminal ganglia as main immunostaining areas, and contralateral involvement in the superior cervical and trigeminal ganglia. Sphenopalatine immunostaining was scarce. 3. The release of neuropeptides in the external jugular vein in humans in the postoperative course after subarachnoid hemorrhage, using radioimmunoassay, was correlated to hemodynamical changes (vasoconstriction) monitored with Doppler ultrasound on middle cerebral (MCA) and internal carotid arteries (ICA)). 4. Neuropeptide Y-like immunoreactivity (NPY-LI) levels were increased compared to controls in patients with hemodynamic changes, and in some patients a relationship was found between velocities and NPY-LI. 5. Calcitonin gene-related peptide-LI levels were also increased in connection with vasospasm. In patients with MCA lesions a correlation of 0.61, p = 0.0002 was found between hemodynamic index (V MCA/V ICA) and CGRP-LI. The possible sympathetic and trigemino-cerebrovascular activation are discussed.

Topics: Animals; Benzofurans; Calcitonin Gene-Related Peptide; Cerebral Arteries; Cerebrovascular Circulation; Haplorhini; Hemodynamics; Humans; Ischemic Attack, Transient; Nerve Fibers; Neuropeptide Y; Neuropeptides; Subarachnoid Hemorrhage; Ultrasonography; Vasoconstriction

Neuropeptide Y exerts profound effects on body weight and glucose homeostasis. We have investigated the effect of centrally administered neuropeptide Y on the activity of descending neurones of the hypothalamic paraventricular nucleus by combining retrograde tract tracing with c-Fos immunocytochemistry. Male rats were injected with True Blue into the dorsal vagal complex and with FluoroGold into the intermediolateral column of the lower thoracic spinal cord. One week after the last surgical procedure, animals were injected centrally with an orexigenic dose of neuropeptide Y (5 microg) and sacrificed 60 to 240 minutes following this injection. Temporal analysis of NPY-induced c-Fos expression showed a peak at 90 minutes, which was nearly returned to basal levels between 120 and 240 minutes. Expression of c-Fos was prominent in several of the subnuclei of the paraventricular nucleus and in the adjacent perifornical nucleus. Neurones projecting to the spinal cord were prominent in the dorsal, lateral, and ventral portion of the medial parvicellular subnuclei of the PVN. About 15% of IML projecting neurones of the medial parvicellular subnucleus were Fos-positive, whereas less than 5% of IML projecting neurones from other subnuclei were Fos-positive. Hardly any PVN neurones projecting to the dorsal vagal complex were concomitantly Fos-positive. A considerably larger (>10%) proportion of perifornical neurones projecting to the nucleus of the solitary tract were c-Fos-immunopositive. In conclusion, NPY induces c-Fos in paraventricular neurones projecting to intermediolateral column of the spinal cord and in neurones of the perifornical nucleus projecting to the dorsal vagal complex.

Topics: Animals; Benzofurans; Efferent Pathways; Fluorescent Dyes; Homeostasis; Immunohistochemistry; Male; Medulla Oblongata; Neurons; Neuropeptide Y; Paraventricular Hypothalamic Nucleus; Proto-Oncogene Proteins c-fos; Rats; Rats, Wistar; Spinal Cord; Stilbamidines; Vagus Nerve

Temporal changes in the appearance and the cell-size spectrum of neuropeptide Y (NPY)-like immunoreactive (IR) cells in the rat trigeminal ganglion (TG) following peripheral axotomy of the inferior alveolar nerve (IAN) were studied by retrograde neuronal tracing with True Blue (TB) and immunohistochemistry for NPY. The number of labeled cells following application of TB to the cut-end of the IAN increased rapidly up to 3 days, and was maintained at a constant level thereafter. The size distribution of cross-sectional areas of TB-labeled cells was similar at 3 days and afterwards. NPY-IR cells, which were not detected in the normal TG, appeared on the first day following axotomy, and increased gradually in number reaching a maximum at 14 days. The frequency histogram of the cross-sectional areas of NPY-IR cells was similar at 3 days and afterwards. The present results indicate that the effect of nerve injury on the levels of NPY expression in the sensory neurons began soon after nerve injury, reaching a maximum around 14 days, and that induction of NPY in the sensory neurons occurred in the same cell size-specific manner for a long period.

Topics: Age Factors; Animals; Axons; Benzofurans; Cell Count; Gene Expression; Immunohistochemistry; Male; Mandibular Nerve; Neurons; Neuropeptide Y; Rats; Rats, Wistar; Time Factors; Trigeminal Ganglion

The effect of peripheral axotomy of the mental nerve (MN) and the cutaneous branch of the mylohyoid nerve (MhN) on the appearance of neuropeptide Y-like immunoreactivity (NPY-IR) in cells in the trigeminal ganglion of the rat was examined with combined retrograde-tracing and immunohistochemistry. Retrograde-tracing with True Blue (TB) revealed that the cell-size spectrum of the trigeminal cells sending peripheral processes to the MN (TB MN cells) ranged from 75.9 to 1560.5 microns2 (or from 9.8 to 44.6 microns in diameter); approximately 53% of TB MN cells were 300-600 microns2. TB MhN cells ranged from 47.7 to 1261.5 microns2 (or from 7.8 to 40.1 microns in diameter); 56% of TB MhN cells were < 300 microns2. In the normal trigeminal ganglion, there were no NPY-IR cells. 14 days after MN transection, approximately 35% of TB MN cells displayed NPY-IR. The distribution of the cross-sectional areas of NPY-IR cells after MN transection was very similar to that of TB MN cells. Transection of MhN also induced the appearance of NPY-IR in the trigeminal ganglion but to a lesser extent (approximately 17% of TB MhN cells). The distribution of the cross-sectional areas of NPY-IR cells after MhN transection was similar to that of NPY-IR cells after MN transection. These results indicate that injury-evoked NPY-IR is specific for the medium- and large-sized ganglion cells.

Topics: Animals; Axonal Transport; Benzofurans; Fluorescein-5-isothiocyanate; Fluorescent Antibody Technique; Fluorescent Dyes; Immunoglobulin G; Immunohistochemistry; Male; Mandibular Nerve; Neuropeptide Y; Rats; Rats, Sprague-Dawley; Skin; Trigeminal Ganglion

The distribution and origin of neuropeptide Y-, vasoactive intestinal peptide- and calcitonin gene-related peptide-containing nerve fibers and adrenergic (dopamine-beta-hydroxylase-containing) fibers in the rat larynx were studied by retrograde tracing and selective denervations in combination with immunocytochemistry. An injection of the retrograde tracer True Blue to the right vocal cord resulted in the appearance of labelled nerve cell bodies in the ipsi- and contralateral superior cervical and stellate ganglia, the thyroid ganglia, the jugular-nodose ganglionic complexes, in the ipsilateral trigeminal and dorsal root ganglia at levels C2 and C3 and in local tracheal ganglia. Judging from the number of labelled nerve cell bodies, the jugular-nodose ganglionic complexes, dorsal root ganglia and superior cervical ganglia provide the greater part of the vocal cord innervation. Most of the True Blue-labelled nerve cell bodies in the superior cervical and stellate ganglia contained neuropeptide Y. In the thyroid ganglia the majority of labelled nerve cell bodies contained vasoactive intestinal peptide. In the jugular-nodose ganglionic complex and the dorsal root ganglia the majority of the labelled nerve cell bodies stored calcitonin gene-related peptide. Retrograde tracing and denervation studies revealed that all noradrenaline- and the majority of neuropeptide Y-containing nerve fibers emanate from the superior cervical and stellate ganglia. A minor population of neuropeptide Y-containing nerve fibers originate in local tracheal ganglia. The vasoactive intestinal peptide-containing nerve fibers originate in the thyroid ganglion and local tracheal ganglia, whereas calcitonin gene-related peptide-containing nerve fibres emanate from the dorsal root ganglia (C2-C3), the trigeminal ganglia and the jugular-nodose ganglia.

Topics: Animals; Benzofurans; Calcitonin Gene-Related Peptide; Dopamine beta-Hydroxylase; Fluorescent Dyes; Immunohistochemistry; Nerve Fibers; Neurons; Neuropeptide Y; Rats; Sympathectomy; Sympathetic Nervous System; Synaptic Transmission; Vasoactive Intestinal Peptide; Vocal Cords

The origin of nerve fibers to the rat middle cerebral artery was studied by retrograde tracing with the fluorescent tracer True Blue (TB) in combination with immunocytochemistry to known perivascular peptides. Application of TB to the middle cerebral artery labeled nerve cell bodies in the ipsilateral superior cervical ganglion, the otic ganglion, the sphenopalatine ganglion, the trigeminal ganglion, and the cervical dorsal root ganglion at level C2. A few labeled nerve cell bodies were seen in contralateral ganglia. Judging from the number and intensity of the labeling, the superior cervical ganglion and the trigeminal ganglion and dorsal root ganglion at level C2 contributed most to the innervation. A moderate number of nerve cell bodies were labeled in the sphenopalatine and otic ganglia. The TB-labeled nerve cell bodies were further examined for the presence of neuropeptides. For that purpose antibodies raised against neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), substance P (SP) and calcitonin gene-related peptide (CGRP) were used. A considerable portion of the TB-labeled nerve cell bodies in the superior cervical ganglion contained NPY. About half of the labeled nerve cell bodies in the sphenopalatine and otic ganglia contained VIP. In the trigeminal ganglion and in the dorsal root ganglion at level C2, one-third of the TB-labeled nerve cell bodies were CGRP-immunoreactive, while only few nerve cell bodies contained SP. The study provides direct evidence for the origin of cerebrovascular peptidergic nerve fibers and demonstrates that not only ipsilateral but also contralateral ganglia contribute to the innervation of the cerebral circulation.

Topics: Animals; Benzofurans; Calcitonin Gene-Related Peptide; Cerebral Arteries; Immunohistochemistry; Nerve Fibers; Neuropeptide Y; Neuropeptides; Rats; Substance P; Vasoactive Intestinal Peptide

Postganglionic perikarya in preaortic ganglia projecting to the ovary of the rat were identified utilizing the retrograde fluorescent tracer, true blue. Ovarian perikarya were subsequently examined for neuropeptide Y and somatostatin immunoreactivity. True blue-labelled ovarian postganglionic perikarya were distributed in the coeliac ganglion and in smaller ganglia located at the origins of the renal and ovarian arteries. In the coeliac ganglia, 74.4 +/- 18.8% of true blue-labelled ovarian perikarya were immunoreactive to neuropeptide Y while 37.4 +/- 9.6% were immunoreactive to somatostatin. In the inferior smaller ganglia, 72.2 +/- 18.7% and 2.2 +/- 2.2% of the true blue-labelled ovarian perikarya were immunoreactive to neuropeptide Y and somatostatin respectively. It is suggested that neuropeptide Y and somatostatin participate in the modulation of ovarian function.

Topics: Animals; Benzofurans; Female; Fluorescent Antibody Technique; Ganglia, Sympathetic; Neurons, Afferent; Neuropeptide Y; Ovary; Rats; Rats, Inbred Strains; Somatostatin