1
|
Kostopoulos GK. The tottering mouse: a critical review of its usefulness in the study of the neuronal mechanisms underlying epilepsy. JOURNAL OF NEURAL TRANSMISSION. SUPPLEMENTUM 1992; 35:21-36. [PMID: 1512593 DOI: 10.1007/978-3-7091-9206-1_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The tottering mouse resulted from a recessively inherited, autosomal, single-locus mutation which produces a very characteristic neurological and cellular phenotype. Almost simultaneously and late in the development of this mutant appears a triad of symptoms: frequent episodes of absence seizures with spike-and-wave discharges; more rarely occurring episodes of focal motor seizures; and ataxia. Electrographic, behavioural and pharmacological similarities to absence epilepsy in man make the tottering mouse a useful animal model for testing new anti-absence drugs. It also affords a unique opportunity to study the effects of multiple alleles on epileptic behaviour. The neuronal mechanisms underlying the generation of absence seizures in this mutant are apparently a combination of a generalized noradrenergic hyperactivity in the brain and some gene-linked, but unknown, conditions prevailing in an earlier phase of development at specific brain areas which induce the generalized forebrain hyper-innervation by locus coeruleus terminals. Several biochemically, microscopically and electrophysiologically identified cellular differences between normal and tottering mice are potential aspects of this primary developmental defect. Research into these gene-linked neuronal characteristics co-inherited with seizures in this mutant makes the tottering mouse a powerful tool in the study of cellular mechanisms underlying genetically determined factors in epileptogenesis.
Collapse
Affiliation(s)
- G K Kostopoulos
- Department of Physiology, Medical School, University of Patras, Greece
| |
Collapse
|
2
|
Abstract
Neurotransmitter receptor binding was analyzed in adult tottering (tg/tg) and control wild-type mice. Saturation studies were performed to analyze the density of muscarinic cholinergic receptors in whole brain, cortical, and hippocampal homogenates of 8-9-week-old animals. Scatchard plot analysis was also performed to determine the density and affinity of alpha-adrenergic and beta-adrenergic receptors. No significant difference in Bmax or Kd values was identified between adult tottering and control mice in any of the tissue preparations. The amount of radioligand binding to 5-hydroxytryptamine 1A (5-HT1A), non-5-HT1A, 5-HT2, dopamine D2, and benzodiazepine receptors was also identical in tottering and control mice. These findings suggest that the epilepsy expressed by adult tottering mice does not result from alterations in the density or affinity of the neurotransmitter receptors studied.
Collapse
Affiliation(s)
- A E Dusser
- Department of Neurology, Stanford University Medical Center, CA 94305
| | | |
Collapse
|
3
|
Lorton D, Bartolome J, Slotkin TA, Davis JN. Development of brain beta-adrenergic receptors after neonatal 6-hydroxydopamine treatment. Brain Res Bull 1988; 21:591-600. [PMID: 2850096 DOI: 10.1016/0361-9230(88)90198-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We used [125I]-cyanopindolol in vitro autoradiography and neonatal 6-hydroxydopamine treatment to study the development of beta-adrenergic receptor subtypes in rat brain. Brain regions receiving locus coeruleus innervation, such as cerebral cortex and cerebellum, displayed low receptor densities at birth and increased in density rapidly during the second and fourth weeks postnatally. By contrast, regions which receive little innervation from the locus coeruleus, such as substantia nigra, striatum, and globus pallidus, displayed relatively high beta-receptor densities even at birth. The striatum appeared to be an exception to these generalizations. 6-Hydroxydopamine administration was associated with an increase in the densities of beta-receptor subtypes and, unexpectedly, with a change in the proportions of the two subtypes. These data support the view that innervation determines the ontogenetic patterns of some receptors in brain.
Collapse
Affiliation(s)
- D Lorton
- Neurology Research Laboratory, V.A. Medical Center, Durham, NC 27705
| | | | | | | |
Collapse
|
4
|
Kostrzewa RM. Reorganization of noradrenergic neuronal systems following neonatal chemical and surgical injury. PROGRESS IN BRAIN RESEARCH 1988; 73:405-23. [PMID: 3138742 DOI: 10.1016/s0079-6123(08)60518-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
5
|
Levitt P, Lau C, Pylypiw A, Ross LL. Central adrenergic receptor changes in the inherited noradrenergic hyperinnervated mutant mouse tottering. Brain Res 1987; 418:174-7. [PMID: 2822204 DOI: 10.1016/0006-8993(87)90976-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Adrenergic receptor binding characteristics were analyzed in the mutant mouse tottering (tg/tg), a single gene locus autosomal recessive mutation causing hyperinnervation by locus coeruleus neurons of their target regions, which results in epilepsy. Instead of the expected down-regulation of receptors due to the hyperinnervation, both [3H]prazosin (alpha 1-receptor) and [125I]iodopindolol (beta-receptor) binding were normal in the tg/tg hippocampus, spinal cord and slightly increased in the cerebellum. This lack of postsynaptic receptor modulation in the target cells, combined with increased levels of norepinephrine due to the aberrant axon growth, may the critical factors in the expression of the abnormal spike-wave absence seizures in the tg/tg mouse.
Collapse
MESH Headings
- Animals
- Brain/metabolism
- Female
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Neurologic Mutants/metabolism
- Norepinephrine/metabolism
- Pindolol/analogs & derivatives
- Pindolol/metabolism
- Prazosin/metabolism
- Receptors, Adrenergic/genetics
- Receptors, Adrenergic/metabolism
- Receptors, Adrenergic, alpha/genetics
- Receptors, Adrenergic, alpha/metabolism
- Receptors, Adrenergic, beta/genetics
- Receptors, Adrenergic, beta/metabolism
- Spinal Cord/metabolism
Collapse
Affiliation(s)
- P Levitt
- Department of Anatomy, Medical College of Pennsylvania, Philadelphia 19129
| | | | | | | |
Collapse
|
6
|
Rhee HM. Kinetic analysis of cardiac beta-receptors in perfused working rabbit hearts. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1986; 200:385-91. [PMID: 3026146 DOI: 10.1007/978-1-4684-5188-7_47] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Myocardial adrenergic beta-receptors were isolated and partially purified from the nonischemic perfused working rabbit hearts. Using highly radioactive beta-receptor antagonist, dihydroalprenolol (DHA), properties of beta-receptors were investigated by kinetic equilibrium analysis when the physiological function of the heart appeared to be normal. At the concentration of 10 nM DHA dissociation constant (Kd) was 14.9 nM and there were at least two distinctly different DHA binding sites, based on the analysis of the dissociation rate of DHA-receptor complex. Identification of the two distinctly different DHA binding sites was not obvious from the analysis of Scatchard plot.
Collapse
|
7
|
Sutin J, Minneman KP. Adrenergic beta receptors are not uniformly distributed in the cerebellar cortex. J Comp Neurol 1985; 236:547-54. [PMID: 2997307 DOI: 10.1002/cne.902360410] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The noradrenergic (NE) innervation of the cerebellar cortex is sparse, forming a broad plexus of radially oriented axons distributing throughout the granular and molecular layers. Autoradiographic studies of beta-adrenergic receptor distribution in the rat show the greatest density of silver grains in the molecular layer (Palacios and Kuhar, '82). In the course of studies of NE hyperinnervated structures, we found that beta receptors are nonhomogeneously distributed in the Purkinje cell layer, where they occur in "patches" overlying small groups of Purkinje cell somata. Tissue sections were incubated in 10 pM 125iodocyanopindolol (ICYP), which binds equally to beta1 and beta2 adrenergic receptors. Nonspecific binding was determined in sections incubated in 125ICYP and 1 microM dl-propranolol. Beta-adrenergic receptor patches are of irregular size and are most prominent in the vermis of lobules I-IX, although the medial cerebellar hemispheres also show areas of increased silver grains over Purkinje cells. In order to determine the subtype of beta receptors, adjacent sections were incubated with either 125ICYP and the beta 2-selective antagonist IPS-339, or 125ICYP and the beta 1-selective antagonist practolol. Patches were observed after each incubation procedure, indicating that they are composed of both beta1 and beta2 receptors. Patches are observed in normal animals and also in rats in which cerebellar NE content was increased 165% by neonatal treatment with 6-hydroxydopamine. This treatment does not alter the density of beta receptors. The cerebellar elements in which the beta receptors are located is not known. While silver grains accumulate over small groups of Purkinje cell somata, they are not coextensive with these cell bodies. The distribution of beta-adrenergic receptors does not parallel the arrangement of noradrenergic varicosities in the rat cerebellar cortex.
Collapse
|
8
|
Maj J, Przegalinski E, Mogilnicka E. Hypotheses concerning the mechanism of action of antidepressant drugs. Rev Physiol Biochem Pharmacol 1984; 100:1-74. [PMID: 6146181 DOI: 10.1007/3540133275_1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
9
|
Sugrue MF. Some effects of chronic antidepressant treatments on rat brain monoaminergic systems. J Neural Transm (Vienna) 1983; 57:281-95. [PMID: 6197507 DOI: 10.1007/bf01248999] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A range of established and putative antidepressant therapies were studied for the effect of their long-term administration on two facets of presynaptic monoaminergic functioning in rat brain, namely NE, DA, and 5-HT turnover and alpha 2-adrenoceptor sensitivity. Unless stated otherwise drugs (10 mg/kg) were injected i.p. twice daily for 14 days. ECT (100 mA for 1 s) was applied once daily for 10 days. Changes in turnover were indirectly assessed by measuring levels of metabolites. Brain levels of MHPG-SO4 were unchanged by chronic amitriptyline, imipramine, nisoxetine (20 mg/kg), nortriptyline, salbutamol (5 mg/kg), and ECT. Amitriptyline elicited a slight, but significant, increase in brain DOPAC content. Brain levels of 5-HIAA were increased by amitriptyline, imipramine, salbutamol, and ECT. An overall view of the results indicates that no common pattern of change was elicited by the range of antidepressant therapies studied. Central alpha 2-adrenoceptor sensitivity was assessed by investigating the effect of various therapies on the ability of clonidine (25 mg/kg i.p.) to decrease rat brain MHPG-SO4 content. The clonidine-induced fall was attenuated by desipramine, imipramine, and ECT. Amitriptyline, iprindole, mianserin, nisoxetine, nortriptyline, Org 6582 (10 mg/kg once daily), pargyline (25 mg/kg once daily), salbutamol, and trazodone were ineffective. The following chronic antidepressant therapies were investigated for their effect on rat frontal cortex 3H-clonidine binding: amitriptyline, desipramine, imipramine, iprindole, mianserin, nisoxetine, nortriptyline, pargyline, salbutamol, and ECT. CHronic, but not acute, pargyline decreased 3H-clonidine binding and this was due to a diminished number of binding sites. The induction of subsensitive presynaptic alpha 2-adrenoceptors in rat brain is not a property common to all forms of antidepressant therapies. Hence it cannot be the fundamental mode of action of antidepressants. No correlation exists between the changes in rat cortical 3H-clonidine binding and the observed changes in the sensitivity of central presynaptic alpha 2-adrenoceptors.
Collapse
|
10
|
Singer HS, Weaver D, Tiemeyer M, Coyle JT. Synaptic chemistry associated with aberrant neuronal development in the reeler mouse. J Neurochem 1983; 41:874-81. [PMID: 6135760 DOI: 10.1111/j.1471-4159.1983.tb04821.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
11
|
|
12
|
Dooley DJ, Hauser KL. Subchronic infusion of clenbuterol, a beta-adrenergic agonist, decreases the cerebellar beta receptor. Neurosci Lett 1983; 36:93-7. [PMID: 6304582 DOI: 10.1016/0304-3940(83)90492-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Subchronic, peripheral infusion of clenbuterol, a beta-adrenergic agonist, markedly reduced beta receptor density and isoproterenol-sensitive adenylate cyclase activity in the cerebellum of the rat. In contrast, infusion of salbutamol, isoproterenol or desipramine did not alter the beta receptor. The result of clenbuterol administration demonstrates, for the first time, a significant alteration of the cerebellar beta 2 receptor to a pharmacologic manipulation. This alteration may influence physiological and behavioral processes regulated by the cerebellum.
Collapse
|
13
|
|
14
|
Beaulieu M, Coyle JT. Fetally-induced noradrenergic hyperinnervation of cerebral cortex results in persistent down-regulation of beta-receptors. Brain Res 1982; 256:491-4. [PMID: 6290000 DOI: 10.1016/0165-3806(82)90195-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Methylazoxymethanol acetate (MAM)-induced cortical hypoplasia resulted in a 2-fold increase in the concentration of norepinephrine and its metabolite, 3-methoxyl-4-hydroxyphenylglycol sulfate, and a 26% decrease in the Bmax for the beta-receptor ligand, [3H]dihydroalprenolol (DHA) in the rat cortex. Chronic treatment with desmethylimipramine did not further decrease DHA-labeled sites although prior lesion of the noradrenergic terminals with 6-hydroxydopamine markedly increased the number in the MAM-lesioned cortex.
Collapse
|
15
|
|
16
|
Wolfe BB, Minneman KP, Molinoff PB. Selective increases in the density of cerebellar beta-1-adrenergic receptors. Brain Res 1982; 234:474-9. [PMID: 6277437 DOI: 10.1016/0006-8993(82)90890-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Destruction of noradrenergic neurons by 6-hydroxydopamine or chronic blockade of beta-adrenergic receptors with propranolol increased the density of beta 1-adrenergic receptors two-fold in rat cerebellum but had no effect on the density of beta 2-adrenergic receptors. The results suggest that even through beta 1 receptors comprise only 5-10% of the total number of Beta-adrenergic receptors in the cerebellum they are the receptors specifically innervated by noradrenergic neurons and they may thus be the physiologically important receptors.
Collapse
|
17
|
Cantor EH, Clark MB, Weiss B. Effect of sympathetic input on ontogeny of beta-adrenergic receptors in rat pineal gland. Brain Res Bull 1981; 7:243-7. [PMID: 6268253 DOI: 10.1016/0361-9230(81)90014-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The ontogeny of beta-adrenergic receptors was investigated in the pineal glands of rats 1-64 days of age. The density of beta-receptors increased about 3-fold between 1 and 16 days of age and decreased slightly by 64 days, correlating temporally with the development of the sensitivity of adenylate cyclase to norepinephrine in pineal gland. Preventing adrenergic innervation of the pineal gland by neonatal ganglionectomy or decentralization failed to prevent the development of beta-adrenergic receptors in pineal gland. Bilateral adrenal demedullation alone or in combination with ganglionectomy also failed to prevent the normal developmental increase of beta-receptors in the gland. These results, showing that the ontogeny of pineal beta-receptors correlated temporally with that of the responsiveness of adenylate cyclase to adrenergic neurohormones, support the hypothesis that the responsiveness of tissues ot beta-agonists is dependent on the development of the beta-receptor. In addition, these experiments show that the beta-adrenergic receptor can develop even in the absence of sympathetic innervation or circulating catecholamines produced by the adrenal medullae.
Collapse
|
18
|
|
19
|
Higgins D, Pappano AJ. Developmental changes in the sensitivity of the chick embryo ventricle to beta-adrenergic agonist during adrenergic innervation. Circ Res 1981; 48:245-53. [PMID: 6109580 DOI: 10.1161/01.res.48.2.245] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
As early as the 4th embryonic day, the ventricle of the chick embryo responded to isoproterenol (Iso) with an increase in the force of contraction; at all ages studied, this positive inotropic effect was accompanied by an increased rate of tension development. There was a transient, 10-fold decrease in the sensitivity (increase in ED50) of the right ventricle to Iso between the 16th and 21st embryonic day. This change in the sensitivity to Iso was not due either to an increased inactivation of Iso by non-neuronal cells or to a change in the thickness of the ventricle. It was found that adrenergic nerves were first capable of altering ventricular contractility on the 16th embryonic day. Whereas they interfered with the function of adrenergic nerves, injections of reserpine or 6-hydroxydopamine had no effect on the subsensitivity to Iso. Furthermore, these agents did not affect the normal developmental changes in heart weight. We conclude that the local release of transmitter from adrenergic nerves does not cause the transient subsensitivity of the ventricle of the chick embryo to beta-adrenergic agonists.
Collapse
|
20
|
Sugrue MF. Effects of acutely and chronically administered antidepressants on the clonidine-induced decrease in rat brain 3-methoxy-4-hydroxyphenylethylene-glycol sulphate content. Life Sci 1981; 28:377-84. [PMID: 6971384 DOI: 10.1016/0024-3205(81)90082-5] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
21
|
|
22
|
Ben-Barak J, Dudai Y. Scopolamine induces an increase in muscarinic receptor level in rat hippocampus. Brain Res 1980; 193:309-13. [PMID: 7378826 DOI: 10.1016/0006-8993(80)90973-7] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
23
|
|
24
|
Levitt P, Moore RY. Organization of brainstem noradrenaline hyperinnervation following neonatal 6-hydroxydopamine treatment in rat. ANATOMY AND EMBRYOLOGY 1980; 158:133-50. [PMID: 7356173 DOI: 10.1007/bf00315901] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|