Abstract
The present study describes the distribution of alpha2-adrenoceptors in the parabrachial and KöllikerFuse nucleus of the rat by employing the tritium-labeled alpha2-receptor antagonist rauwolscine ([3H]-RAUW) as a ligand. The [3H]-RAUW binding was densitometrically quantified in five nuclei of the parabrachial (PB) complex in serial coronal sections. We found that cytoarchitectonically and anatomically distinct nuclei of the PB complex exhibit different numbers of [3H]-RAUW-binding sites. The largest number of binding sites was observed over the external lateral PB and caudally over the waist area of the PB. Lower numbers of binding sites were found in the remaining lateral PB nuclei, followed by the medial PB and the Kölliker-Fuse nucleus. In addition we disclosed that the internal lateral PB contains a very low number of binding sites while the external medial PB is marked by dense [3H]-RAUW binding. Also, the affinities of the binding sites differed between the PB areas. High affinities were observed in the external lateral PB, the remaining lateral PB nuclei and in the waist area of the PB, while the medial PB and the KöllikerFuse nucleus exhibited only low affinities for the ligand. Furthermore, saturation curves demonstrated non-linear profiles, indicating the presence of more than one population of binding sites in the PB nuclei for the radioligand. Our data demonstrate that the PB exhibits a distinct distribution of alpha2-adrenergic binding sites. These correlate well with the cytoarchitectonically defined nuclei of the PB complex and with the pattern of ascending axons from the medial nucleus of the solitary tract and the area postrema terminating in the PB. Since a large number of these projection neurons utilize adrenaline or noradrenaline as their transmitters, we conclude that solitary-parabrachial neurotransmission to the forebrain is, at least in part, mediated via alpha2-adrenoceptors.
Similar content being viewed by others
References
Alden M, Besson J-M, Bernard J-F (1994) Organization of the efferent projections from the pontine parabrachial area to the bed nucleus of the stria terminalis and neighboring regions: a PHA-L study in the rat. J Comp Neurol 341:289–314
Allen AM, Guyenet PG (1993) α2-adrenoceptor-mediated inhibition of bulbospinal barosensitive cells of rat rostral medulla. Am J Physiol 265:R1065-R1075
Allen GV, Zhou J, Hopkins DA (1995) Monoamines in the parabrachial nucleus of the cardiomyopathic hamster. Brain Res 680:117–127
Aoki C, Go CG, Venkatesan C, Kurose H (1994) Perikaryal and synaptic localization of α2A-adrenergic receptor-like immunoreactivity. Brain Res 650:181–204
Bernard J-F, Besson J-M (1990) The spino(trigemmo)pontoamygdaloid pathway: electrophysiological evidence for an involvement in pain processes. J Neurophysiol 63:473–490
Bernard J-F, Alden M, Besson J-M (1993) The organization of the efferent projections from the pontine parabrachial area to the amygdaloid complex: a Phaseolus vulgaris leucoagglutinin (PHA-L) study in the rat. J Comp Neurol 329:201–229
Bernard J-F, Huang G-F, Besson J-M (1994) The parabrachial area: electrophysiological evidence for an involvement in visceral nociceptive processes. J Neurophysiol 71:1646–1660
Block CH, Hoffman GE (1987) Neuropeptide and monoamine components of the parabrachial pontine complex. Peptides 8:267–283
Boyajian CL, Loughlin SE, Leslie FM (1987) Anatomical evidence for alpha-2 adrenoceptor heterogeneity: differential autoradiographic distributions of [3H]rauwolscine and [3H]idazoxan in rat brain. J Pharmacol Exp Ther 241:1079–1091
Bullitt E (1990) Expression of C-fos-like protein as a marker for neuronal activity following noxious stimulation in the rat. J Comp Neurol 296:517–530
Capuano CA, Leibowitz SF, Barr GA (1992) The pharmaco-ontogeny of the paraventricular α2-noradrenergic receptor system mediating norepinephrine-induced feeding in the rat. Dev Brain Res 68:67–74
Cechetto DF, Saper CB (1987) Evidence for a viscerotopic sensory representation in the cortex and thalamus in the rat. J Comp Neurol 262:27–45
Chamberlin NL, Saper CB (1992) Topographic organization of cardiovascular responses to electrical and glutamate microstimulation of parabrachial nucleus in the rat. J Comp Neurpl 326:245–262
Chamberlin NL, Saper CB (1994) Topographic organization of respiratory responses to glutamate microstimulation of the parabrachial nucleus in the rat. J Neurosci 14:6500–6510
Chiang CY, Hu JW, Sessle BJ (1994) Parabrachial area and nucleus raphe magnus-induced modulation of nociceptive and nonnociceptive trigeminal subnucleus caudalis neurons activated by cutaneous or deep inputs. J Neurophysiol 71:2430–2445
DeSalles AAF, Katayama Y, Becker DP, Hayes RL (1985) Pain suppression induced by electrical stimulation of the pontine parabrachial region. J Neurosurg 62:397–407
Feil K, Herbert H (1995) Topographic organization of spinal and trigeminal somatosensory pathways to the rat parabrachial and Kölliker-Fuse nuclei. J Comp Neurol 353:506–528
Flügge G, Jurdzinski A, Fuchs E (1990) Alpha2-adrenergic binding sites in the medulla oblongata of tree shrews demonstrated by in vitro autoradiography: species related differences in comparison to the rat. J Comp Neurol 297:253–266
Fritschy J-M, Grzanna R (1990) Demonstration of two separate descending noradrenergic pathways to the rat spinal cord: evidence for an intragriseal trajectory of locus coeruleus axons in superficial layers of the dorsal horn. J Comp Neurol 291:553–582
Fulwiler CE, Saper CB (1984) Subnuclear organization of the efferent connections of the parabrachial nucleus in the rat. Brain Res Rev 7:229–259
Geary WA, Toga AW, Wooten GF (1985) Quantitative film autoradiography for tritium: methodological considerations. Brain Res 337:99–108
Gillis RA, Gatti PJ, Quest JA (1985) Mechanism of the antihypertensive effect of alpha2-agonists. J Cardiovasc Pharmacol 7:S38-S44
Gunion MW, Rosenthal MJ, Miller S, Hoyt MA, Yonzon DB (1992) Role of hypothalamic paraventricular nucleus α- and β-adrenergic receptors in regulation of blood glucose, free fatty acids and corticosterone. Brain Res 588:84–96
Guyenet PG, Stornetta RL, Riley T, Norton FR, Rosin DL, Lynch KR (1994) Alpha2A-adrenergic receptors are present in lower brainstem catecholaminergic and serotonergic neurons innervating spinal cord. Brain Res 638:285–294
Handa RJ, Resko JA (1989) α-adrenergic regulation of androgen receptor concentration in the preoptic area of the rat. Brain Res 483:312–320
Häusler G (1982) Central α-adrenoceptors involved in cardiovascular regulation. J Cardiovasc Pharmacol 4:S72-S76
Herbert H, Bellintani-Guardia B (1995) Morphology and dendritic domains of neurons in the lateral parabrachial nucleus of the rat. J Comp Neurol 354:377–394
Herbert H, Saper CB (1990) Cholecystokinin-, galanin-, and corticotropin-releasing factor-like immunoreactive projections from the nucleus of the solitary tract to the parabrachial nucleus in the rat. J Comp Neurol 293:581–598
Herbert H, Flügge G, Fuchs E (1990a) Subnuclear distribution of alpha2-binding sites in the rat parabrachial nucleus. Soc Neurosci Abstr 16:384
Herbert H, Moga MM, Saper CB (1990b) Connections of the parabrachial nucleus with the nucleus of the solitary tract and the medullary reticular formation in the rat. J Comp Neurol 293:540–580
Kachidian P, Pickel VM (1993) Localization of tyrosine hydroxylase in neuronal targets and efferents of the area postrema in the nucleus tractus solitarii of the rat. J Comp Neurol 329:337–353
Kitamura T, Yamada J, Sato H, Yamashita K (1993) Cells of origin of the spinoparabrachial fibers in the rat: a study with fast blue and WGA-HRP. J Comp Neurol 328:449–461
Lantéri-Minet M, Isnardon P, DePommery J, Menétrey D (1993) Spinal and hindbrain structures involved in visceroception and visceronociception as revealed by the expression of Fos, Jun and Krox-24 proteins. Neuroscience 55:737–753
Lara JP, Parkes MJ, Silva-Carvhalo L, Izzo P, Dawid-Milner MS, Spyer KM (1994) Cardiovascular and respiratory effects of stimulation of cell bodies of the parabrachial nuclei in the anaesthetized rat. J Physiol (Lond) 477:321–329
Loewy AD, Burton H (1978) Nuclei of the solitary tract: efferent projections to the lower brain stem and spinal cord of the cat. J Comp Neurol 181:421–450
Lovick TA (1993) Integrated activity of cardiovascular and pain regulatory systems: role in adaptive behavioural responses. Prog Neurobiol 40:631–644
Mantyh PW, Hunt SP (1984) Neuropeptides are present in projection neurones at all levels in visceral and taste pathways: from periphery to sensory cortex. Brain Res 299:297–311
Marjamäki A, Luomala K, Ala-Uotila S, Scheinin M (1993) Use of recombinant human α2-adrenoceptors to characterize subtype selectivity of antagonist binding. Eur J Pharmacol — Molec Pharmacol Sec 246:219–226
Maze M, Tranquilli W (1991) Alpha-2 adrenoceptor agonists: defining the role in clinical anesthesia. Anesthesiology 74:581–605
Mccune SK, Voigt MM, Hill JM (1993) Expression of multiple alpha adrenergic receptor subtype messenger RNAs in the adult rat brain. Neuroscience 57:143–151
Menétrey D, DePommery J (1991) Origins of spinal ascending pathways that reach central areas involved in visceroception and visceronociception in the rat. Eur J Neurosci 3:249–259
Millan MJ (1992) Evidence that an α2A-adrenoceptor subtype mediates antinociception in mice. Eur J Pharmacol 215:355–356
Millan MJ, Colpaert FC (1991) α2 receptors mediate the antinociceptive action of 8-OH-DPAT in the hot-plate test in mice. Brain Res 539:342–346
Milner TA, Joh TH, Miller RJ, Pickel VM (1984) Substance P, neurotensin, enkephalin, and catecholamine-synthesizing enzymes: light microscopic localizations compared with autoradiographic label in solitary efferents to the rat parabrachial region. J Comp Neurol 226:434–447
Milner TA, Joh TH, Pickel VM (1986) Tyrosine hydroxylase in the rat parabrachial region: ultrastructural localization and extrinsic sources of immunoreactivity. J Neurosci 6:2585–2603
Moga MM, Herbert H, Hurley KM, Yasui Y, Gray TS, Saper CB (1990) Organization of cortical, basal forebrain, and hypothalamic afferents to the parabrachial nucleus in the rat. J Comp Neurol 295:624–661
Nicholas AP, Pieribone VA, Hökfelt T (1993) Distributions of mRNAs for alpha-2 adrenergic receptor subtypes in rat brain: an in situ hybridization study. J Comp Neurol 328:575–594
Ockert DM, Czachurski J, Dembowsky K, Seller H (1992) Central action of α-adrenoceptor agents on the baroreceptor reflex. J Auton Nerv Syst 41:93–102
Palacios JM, Wamsley JK (1984) Catecholamine receptors. In: Björklund A, Hökfelt T, Kuhar MJ (eds) Handbook of chemical neuroanatomy, vol 3. Classical transmitters and transmitter receptors in the CNS, part II. Elsevier, Amsterdam, pp 325–351
Perälä M, Hirvonen H, Kalimo H, Ala-Uotila S, Regan JW, Åkerman KEO, Scheinin M (1992) Differential expression of two α2-adrenergic receptor subtype mRNAs in human tissues. Mol Brain Res 16:57–63
Pertovaara A (1993) Antinociception induced by alpha-2-adrenoceptor agonists, with special emphasis on medetomidine studies. Prog Neurobiol 40:691–709
Pertovaara A, Bravo R, Herdegen T (1993) Induction and suppression of immediate-early genes in the rat brain by selective alpha-2-adrenoceptor agonist and antagonist following noxious peripheral stimulation. Neuroscience 54:117–126
Pickel VM, Armstrong DM (1984) Ultrastructural localization of monoamines and peptides in rat area postrema. Fed Proc 43:2949–2951
Randich A, Maixner W (1984) Interactions between cardiovascular and pain regulatory systems. Neurosci Biobehav Rev 8:343–367
Reddy SVR, Maderdrut JL, Yaksh TL (1980) Spinal cord pharmacology of adrenergic agonist-mediated antinociception. J Pharmacol Exp Ther 213:525–533
Ricardo JA, Koh ET (1978) Anatomical evidence of direct projections from the nucleus of the solitary tract to the hypothalamus, amygdala, and other forebrain structures in the rat. Brain Res 153:1–26
Riche D, DePommery J, Menétrey D (1990) Neuropeptides and catecholamines in efferent projections of the nuclei of the solitary tract in the rat. J Comp Neurol 293:399–424
Rosin DL, Zeng D, Stornetta RL, Norton FR, Riley T, Okusa MD, Guyenet PG, Lynch KR (1993) Immunohistochemical localization of α2A-adrenergic receptors in catecholaminergic and other brainstem neurons in the rat. Neuroscience 56:139–155
Roudet C, Mouchet P, Feuerstein C, Savasta M (1994) Normal distribution of alpha 2-adrenoceptors in the rat spinal cord and its modification after noradrenergic denervation: a quantitative autoradiographic study. J Neurosci Res 39:319–329
Saleh TM, Cechetto DF (1994) Neurotransmitters in the parabrachial nucleus mediating visceral input to the thalamus in the rat. Am J Physiol 266:R1287-R1296
Scheinin M, Lomasney JW, Hayden-Hixson DM, Schambra UB, Caron MG, Lefkowitz RJ, Fremeau RT (1994) Distribution of α2-adrenergic receptor subtype gene expression in rat brain. Mol Brain Res 21:133–149
Smythe GA, Edwards SR (1991) A role for central postsynaptic α2-adrenoceptors in glucoregulation. Brain Res 562:225–229
Stone EA, Ariano MA (1989) Are glial cells targets of the central noradrenergic system? A review of the evidence. Brain Res Rev 14:297–309
Sumal KK, Blessing WW, Job TH, Reis DJ, Pickel VM (1983) Synaptic interaction of vagal afferents and catecholaminergic neurons in the rat nucleus tractus solitarius. Brain Res 277:31–40
Sved AF, Tsukamoto K, Schreihofer AM (1992) Stimulation of α2-adrenergic receptors in nucleus tractus solitarius is required for the baroreceptor reflex. Brain Res 576:297–303
Torvik A (1956) Afferent connections to the sensory trigeminal nuclei, the nucleus of the solitary tract and adjacent structures: an experimental study in the rat. J Comp Neurol 106:51–141
Unnerstall JR, Kuhar MJ (1988) 5. Mapping the α-adrenergic receptor in the central nervous system: a guide to structure and function. In: Stolk JM, U'Prichard DC, Fuxe K (eds) Epinephrine in the central nervous system. Oxford University Press, New York, pp 45–59
Unnerstall JR, Kopajtic TA, Kuhar MJ (1984) Distribution of α2 agonist-binding sites in the rat and human central nervous system: analysis of some functional, anatomical correlates of the pharmacologic effects of clonidine and related adrenergic agents. Brain Res Rev 7:69–101
Wamsley JK, Alburges ME, Hunt MA, Bylund DB (1992) Differential localization of α2-adrenergic receptor subtypes in brain. Pharm Biochem Behav 41:267–273
Zeng D, Lynch KR (1991) Distribution of α2-adrenergic receptor mRNAs in the rat CNS. Mol Brain Res 10:219–225
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Herbert, H., Flügge, G. Distribution of alpha2-adrenergic binding sites in the parabrachial complex of the rat. Anat Embryol 192, 507–516 (1995). https://doi.org/10.1007/BF00187181
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00187181