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Jin LQ, Wang HY, Friedman E. Stimulated D(1) dopamine receptors couple to multiple Galpha proteins in different brain regions. J Neurochem 2001; 78:981-90. [PMID: 11553672 DOI: 10.1046/j.1471-4159.2001.00470.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previous studies have revealed that activation of rat striatal D(1) dopamine receptors stimulates both adenylyl cyclase and phospholipase C via G(s) and G(q), respectively. The differential distribution of these systems in brain supports the existence of distinct receptor systems. The present communication extends the study by examining other brain regions: hippocampus, amygdala, and frontal cortex. In membrane preparations of these brain regions, selective stimulation of D(1) dopamine receptors increases the hydrolysis of phosphatidylinositol/phosphatidylinositol 4,5-biphosphate. In these brain regions, D(1) dopamine receptors couple differentially to multiple Galpha protein subunits. Antisera against Galpha(q) blocks dopamine-stimulated PIP(2) hydrolysis in hippocampal and in striatal membranes. The binding of [(35)S]GTPgammaS or [alpha-(32)P]GTP to Galpha(i) was enhanced in all brain regions. Dopamine also increased the binding of [(35)S]GTPgammaS or [alpha-(32)P]GTP to Galpha(q) in these brain regions: hippocampus = amygdala > frontal cortex. However, dopamine-stimulated binding of [(35)S]GTPgammaS to Galphas only in the frontal cortex and striatum. This differential coupling profile in the brain regions was not related to a differential regional distribution of the Galpha proteins. Dopamine induced increases in GTPgammaS binding to Galpha(s) and Galpha(q) was blocked by the D(1) antagonist SCH23390 but not by D(2) receptor antagonist l-sulpiride, suggesting that D(1) dopamine receptors couple to both Galpha(s) and Galpha(q) proteins. Co-immunoprecipitation of Galpha proteins with receptor-binding sites indicate that in the frontal cortex, D(1) dopamine-binding sites are associated with both Galpha(s) and Galpha(q) and, in hippocampus or amygdala, D(1) dopamine receptors couple solely to Galpha(q). The results indicate that in addition to the D(1)/G(s)/adenylyl cyclase system, brain D(1)-like dopamine receptor sites activate phospholipase C through Galpha(q) protein.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Amygdala/metabolism
- Animals
- Benzazepines/pharmacology
- Brain/metabolism
- Cell Membrane/metabolism
- Dopamine/pharmacology
- Dopamine Agonists/pharmacology
- Dopamine Antagonists/pharmacology
- Frontal Lobe/metabolism
- GTP-Binding Protein alpha Subunits, Gq-G11
- GTP-Binding Protein alpha Subunits, Gs/analysis
- GTP-Binding Protein alpha Subunits, Gs/metabolism
- Guanosine 5'-O-(3-Thiotriphosphate)/pharmacology
- Heterotrimeric GTP-Binding Proteins/analysis
- Heterotrimeric GTP-Binding Proteins/metabolism
- Hippocampus/metabolism
- Male
- Phosphatidylinositols/metabolism
- Phosphorus Radioisotopes
- Precipitin Tests
- Rats
- Rats, Sprague-Dawley
- Receptors, Dopamine D1/analysis
- Receptors, Dopamine D1/metabolism
- Sulfur Radioisotopes
- Tritium
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Affiliation(s)
- L Q Jin
- Laboratory of Molecular Pharmacology, Department of Pharmacology and Physiology, MCP Hahnemann School of Medicine, Philadelphia 19102, USA
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2
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Tasca CI, Vendite D, Garcia KL, Souza DO. Effects of adenosine on cAMP production during early development in the optic tectum of chicks. Int J Dev Neurosci 1995; 13:545-53. [PMID: 8553889 DOI: 10.1016/0736-5748(95)00047-k] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Accumulation of cyclic adenosine monophosphate (cAMP) elicited by adenosine was studied in slices and membrane preparations of optic tectum from chicks aged 1-13 days post-hatch. Accumulation of cAMP promoted by adenosine declined with age, the highest value being observed in three-day-old chicks and the lowest in 11-day-old chicks. However, when the slices were incubated with adenosine and the phosphodiesterase inhibitor-Ro 20-1724 the differences between the two ages were abolished, suggesting a higher phosphodiesterase activity in 11-day-old chicks. In membrane preparations, although basal adenylate cyclase activity was lower in three-day-old chicks, the guanylyl-imidodiphosphate (Gpp(NH)p) concentration curves for stimulation of adenylate cyclase activity indicated a higher sensitivity of G protein to Gpp(NH)p at this age. This hypothesis was reinforced by the observation that the binding of [3H]Gpp(NH)p to the membrane preparation was greater in three-day-old animals. In spite of these differences, the percentage of adenylate cyclase activity stimulation by 2-chloroadenosine (2CADO)+Gpp(NH)p was the same at both ages. These findings suggest that the decreased response evoked by adenosine during development is probably due to increased phosphodiesterase activity and a lower sensitivity of adenylate cyclase activity to Gpp(NH)p.
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Affiliation(s)
- C I Tasca
- Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
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3
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Pihoker C, Cain ST, Nemeroff CB. Postnatal development of regional binding of corticotropin-releasing factor and adenylate cyclase activity in the rat brain. Prog Neuropsychopharmacol Biol Psychiatry 1992; 16:581-6. [PMID: 1641499 DOI: 10.1016/0278-5846(92)90063-k] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. Corticotropin-releasing factor (CRF) plays a major role in the endocrine, autonomic and behavioral responses to stress. The distribution of CRF and CRF receptors in hypothalamic and extra-hypothalamic brain regions is consistent with its stress-related functions. 2. In most brain regions, CRF acts primarily, if not exclusively, through activation of the adenylate cyclase systems. 3. While previous studies have demonstrated the prenatal presence of CRF receptors, in the early postnatal period the abundance of CRF receptors relative to the magnitude of CRF-stimulated cAMP production suggests that CRF receptors are not fully linked to adenylate cyclase. 4. Because of our interest in the possible involvement of CRF signal transduction in the development of the neonatal stress response, we have examined postnatal development of CRF receptors in relation to adenylate cyclase activity in the rat. 5. CRF binding decreased significantly in the hippocampus and striatum from postnatal days 7-21. Basal adenylate cyclase activity peaked in the second-third week of postnatal life in each brain region. Preliminary studies suggest that early stress can alter the maturation of second messenger systems in the frontal cortex.
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Affiliation(s)
- C Pihoker
- Department of Psychiatry, Duke University Medical Center, Durham, NC
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4
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Munaro NI, Taleisnik S. A cyclic AMP mechanism mediates the serotonin-induced increase in glutamic acid decarboxylase activity in the preoptic area and hypothalamus. J Neurochem 1992; 59:206-9. [PMID: 1319466 DOI: 10.1111/j.1471-4159.1992.tb08892.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Previous studies have shown that the injection of 5-hydroxytryptamine (5-HT) into the third ventricle of rats on the afternoon of proestrus increases glutamic acid decarboxylase (GAD) activity in the preoptic area and the hypothalamus. In the present report we examine the adenylate cyclase-cyclic AMP (cAMP) system as mediator of that effect. The increase in GAD activity induced by intraventricular injection of 5-HT was completely blocked by injecting an antiserum against cAMP into the third ventricle 30 min earlier, whereas an injection of serum from normal rabbits was ineffective. On the contrary, activation of adenylate cyclase activity by intraventricular injection of forskolin increased GAD activity, an effect that was also blocked by anti-cAMP serum. Anti-cAMP serum also lowered GAD activity in the preoptic area and hypothalamus when injected on the morning of proestrus but not when injected in the afternoon, when the values of GAD activity were already low. The results suggest that a cAMP mechanism may be involved in the changes in preoptic-area and hypothalamic GAD activity such as the rise in enzyme activity induced by intraventricular injection of 5-HT.
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Affiliation(s)
- N I Munaro
- Instituto de Investigación Médica Mercedes y Martin Ferreyra, Córdoba, Argentina
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5
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Ma FH, Ohkuma S, Kishi M, Kuriyama K. Ontogeny of beta-adrenergic receptor-mediated cyclic AMP generating system in primary cultured neurons. Int J Dev Neurosci 1991; 9:347-56. [PMID: 1659119 DOI: 10.1016/0736-5748(91)90056-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The developmental changes in the beta-adrenergic receptor/cyclic AMP generating system were examined using mouse cerebral cortical neurons in primary culture. During neuronal growth in vitro, the number of binding sites for [3H]dihydroalprenolol (DHA) showed a tendency to increase (Bmax), while the affinity (Kd) for [3H]DHA did not show any noticeable changes. Basal and isoproterenol-stimulated adenylate cyclase activities as well as the activation of adenylate cyclase by 5'-guanylylimidodiphosphate (GppNHp), NaF and forskolin showed progressive and parallel increases during neuronal growth on a polylysine-coated surface. The treatment of primary cultured neurons with islet-activating protein (IAP), one of the pertussis toxins, attenuated the inhibitory effect of carbachol, a muscarinic agonist, on isoproterenol-induced activation of adenylate cyclase activity. These results indicate that primary cultured neurons possess a cyclic AMP generating system coupled with beta-adrenergic and muscarinic receptors, which is regulated via stimulatory and inhibitory GTP-binding proteins, respectively. The results described above also suggest that the beta-adrenergic receptor, stimulatory and inhibitory types of GTP-binding proteins and adenylate cyclase may develop in a parallel fashion during neuronal growth on a polylysine-coated surface.
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Affiliation(s)
- F H Ma
- Department of Pharmacology, Kyoto Prefectural University of Medicine, Japan
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6
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Smith DA, Gallager DW. Electrophysiological and biochemical characterization of the development of alpha 1-adrenergic and 5-HT1 receptors associated with dorsal raphe neurons. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1989; 46:173-86. [PMID: 2541945 DOI: 10.1016/0165-3806(89)90281-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Electrophysiological and quantitative autoradiographic receptor binding approaches were used to characterize the postnatal development of alpha 1-adrenergic and serotonergic receptors in the midbrain dorsal raphe nucleus (DRN) in rats. Dose-response data were obtained from extracellular records of the firing of DRN neurons recorded in midbrain slices perfused with artificial cerebral spinal fluid containing varying concentrations of the drugs investigated. These data indicated that DRN neurons, at all postnatal ages, are equally sensitive to the excitatory effects of phenylephrine (an alpha 1-norepinephrine agonist) and the inhibitory effects of serotonin (5-HT). In contrast, LSD (a 5-HT agonist) was considerably more potent in neonates as compared to adults. With one exception, the autoradiographic binding data was found to be in agreement with the electrophysiological findings. There were no observed changes in the number of alpha 1-adrenergic ([3H]prazosin) binding sites at different ages suggesting that cells in this region exhibit functionally mature alpha 1-adrenergic responses at birth. Similarly, the number of [3H]LSD binding sites was found to increase in older animals consistent with the increased potency of LSD in older animals. Paradoxically, the number of [3H]5-HT sites was observed to increase with age, a finding inconsistent with the functional data obtained using 5-HT in the slice. Hypotheses for the observed discrepancy are examined.
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Affiliation(s)
- D A Smith
- Yale University School of Medicine, Department of Psychiatry, New Haven, CT 06508
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7
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Giorgi O, De Montis G, Porceddu ML, Mele S, Calderini G, Toffano G, Biggio G. Developmental and age-related changes in D1-dopamine receptors and dopamine content in the rat striatum. Brain Res 1987; 432:283-90. [PMID: 2960426 DOI: 10.1016/0165-3806(87)90053-8] [Citation(s) in RCA: 153] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The relationship between the postnatal development of dopaminergic (DAergic) nerve endings and the maturation of D1 DA receptors in the rat striatum was analyzed by measuring the content of DA and dihydroxyphenylacetic acid (DOPAC), two biochemical markers of DAergic nerve terminal proliferation, and the ontogenetic changes in [3H]SCH 23390 binding sites. DA-stimulated adenylate cyclase (AC) activity was also measured in order to characterize the coupling of [3H]SCH 23390 binding sites to the responses mediated by the activation of D1 DA receptors. Striatal levels of DA and DOPAC, as well as the density and affinity of [3H]SCH 23390 binding sites and DA-stimulated AC activity were also measured in senescent rats. The striatal content of DA increased slowly after birth, reaching adult levels by postnatal day 60 and remaining constant through adulthood and senescence (up to 20 months of age). The density of [3H]SCH 23390 binding sites increased 14-fold from birth to postnatal day 35, when a peak value was reached, whereas a significant decrease was observed in the striatum of aged rats. In contrast, the affinity of D1 DA receptors for [3H]SCH 23390 remained unchanged from birth through senescence. The stimulation of cyclic AMP formation induced by 100 microM DA increased 4-fold from birth to postnatal day 14, when the maximal responsiveness to DA was observed and then returned to adult levels. No significant alterations were observed in the Km values during development, whereas the stimulatory effect of 100 microM DA on AC activity was significantly decreased in senescent rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- O Giorgi
- Department of Experimental Biology, University of Cagliari, Italy
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8
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Conn PJ, Sanders-Bush E. Central serotonin receptors: effector systems, physiological roles and regulation. Psychopharmacology (Berl) 1987; 92:267-77. [PMID: 2819915 DOI: 10.1007/bf00210830] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Radioligand binding studies have revealed four distinct serotonin (5HT) binding sites in rat brain that are thought to function as 5HT receptors. These include the 5HT-1a, 5HT-1b, 5HT-1c, and 5HT-2 binding sites. Studies have shown that the 5HT-2 binding site mediates a number of effects of 5HT agonists and serves as a 5HT receptor in neuronal and non-neuronal tissues. The 5HT-2 site employs phosphoinositide hydrolysis for signal transduction. The 5HT-1c binding site is also a functional receptor that is linked to phosphoinositide hydrolysis. However, the physiological role of the 5HT-1c receptor is not yet known. Lack of appropriate pharmacological tools for probing the 5HT-1a and 5HT-1b binding sites has made it difficult to definitively determine whether these binding sites are coupled to biochemical effector systems or mediate any of the physiological responses to 5HT agonists. However, there is some evidence that the 5HT-1a site is coupled to adenylate cyclase, and a number of functional roles for the 5HT-1a and 5HT-1b sites have been proposed.
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9
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Lucot JB, Seiden LS. Effects of serotonergic agonists and antagonists on the locomotor activity of neonatal rats. Pharmacol Biochem Behav 1986; 24:537-41. [PMID: 3486425 DOI: 10.1016/0091-3057(86)90554-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The locomotor activity of neonatal rats was measured after treatment with serotonin agonists or antagonists. Treatment with the serotonin agonists 5-hydroxytryptophan or quipazine resulted in the elimination of the peak in activity which normally results from increases in activity from days 10 to 15 of life followed by decreases from days 15 to 20 of life. The drug-induced decreases in activity occurred at doses that did not alter locomotor activity after day 17, when most of the peak in activity had passed. The dose of 5 mg/kg of the serotonergic antagonist methysergide eliminated the peak in activity without changing locomotor activity after the peak had passed. The antagonists methiothepin and cinanserin only produced decreases in locomotor activity which did not appear to be related to the peak in activity. The serotonergic agonist data are compatible with the hypothesis that the development of the serotonin system contributed to the inhibition of locomotor activity. The methiothepin and cinanserin data neither confirm nor dispute the hypothesis, as their effects may have been either nonserotonergic or on serotonin receptors that were different than those acted on by the agonists.
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10
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Amur SG, Shanker G, Pieringer RA. Beta-adrenergic stimulation of protein (arginine) methyltransferase activity in cultured cerebral cells from embryonic mice. J Neurosci Res 1986; 16:377-86. [PMID: 2876108 DOI: 10.1002/jnr.490160205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Several adrenergic effectors and neurotransmitters were tested as potential regulators of myelin basic protein (MBP) and histone methyltransferase activities. Both enzymes were specifically activated by beta-adrenergic agonists in a stereospecific manner. Cyclic AMP (but not AMP) stimulated the enzymes to the same extent as did the beta-adrenergic agonist, (-) isoproterenol. The studies suggest that beta-adrenergic agonists stimulate adenylate cyclase thereby causing an increased production of cyclic AMP which stimulates the methyltransferases. Cycloheximide addition to the reaction mixture did not affect the stimulation due to cyclic AMP, indicating that new protein synthesis is not involved in the cyclic AMP stimulation of the methyltransferases. Thyroid hormone (T3) has been shown to stimulate MBP methyltransferase [Amur et al, 1984] and could exert its stimulatory effect through beta-adrenergic-dependent systems. But the beta-adrenergic antagonist, propranolol, did not block the stimulation by T3, suggesting that the effect of T3 is not mediated through beta-adrenergic-dependent systems. Thus, the methylation of MBP seems to be regulated both by T3 and by neurotransmitters and/or hormones mediating their effects through cyclic AMP production, whereas the methylation of histones seems to be regulated only by the latter.
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11
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Shanker G, Pieringer RA. Developmental study on the regulation of neurotransmitter-sensitive adenylate cyclase systems in primary cerebral cell cultures from embryonic mice. Biosci Rep 1985; 5:601-8. [PMID: 2864090 DOI: 10.1007/bf01117073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
An ontogenetic study of the effect of various neurohormones and other activators on adenylate cyclase systems was carried out using cultures of cells from 15-d-old embryonic mouse brain. Dopamine stimulated the enzyme activity at earlier culture ages (i.e. 4 and 10 d) but had little stimulatory effect at later ages (i.e. 20 and 33 d). Further, this stimulation at the earlier ages was blocked by the dopaminergic blocker, fluphenazine, but not by alpha and beta-adrenergic antagonists. In contrast to dopamine, isoproterenol (a beta-adrenergic agonist) had little stimulatory effect at earlier ages, but its ability to stimulate cyclase activity increased with age. This increase in all age groups was blocked by propranolol (a beta-adrenergic antagonist). Epinephrine-sensitive enzyme activity showed a steady increase with age, which could be blocked with propranolol except in 4-d-old cultures, where it was blocked instead by fluphenazine. Because the cultures are relatively enriched in neurons at earlier ages and in glia in later ages, the results suggest a predominantly neuronal localization for the dopamine sensitive adenylate cyclases and a glial localization of the isoproterenol and epinephrine sensitive adenylate cyclases. Histamine, serotonin, calcium/calmodulin and chloroadenosine were either only slightly or not at all stimulatory.
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12
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Abstract
Neonatal rat pups given the serotonergic agonist quipazine exhibited alterations in the frequency of several behaviors including an increase in mouthing, forward locomotion, forelimb paddling, unusual position of limbs (UPL), and a decrease in twitching and lying still. The serotonergic antagonist metergoline potently blocked quipazine-induced mouthing and UPL, and partially attenuated the increase in forward locomoting and decrease in lying still induced by quipazine. Pretreatment with the alpha-noradrenergic antagonist phentolamine partially attenuated the quipazine-induced increase in mouthing, with both phentolamine and the dopaminergic antagonist haloperidol exhibiting some tendency to suppress the forward locomotion induced by quipazine. Thus, serotonin appears to be most important for the expression of quipazine-induced behaviors in the neonate, although there appears to be some catecholaminergic involvement as well. While quipazine may induce in neonates some components of the adult "serotonergic syndrome" [8], there are some clear age differences in the response patterns. Serotonergically-influenced behaviors seen only early in ontogeny may subserve adaptive functions for the young organism.
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13
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Ristine LA, Spear LP. Effects of serotonergic and cholinergic antagonists on suckling behavior of neonatal, infant, and weanling rat pups. BEHAVIORAL AND NEURAL BIOLOGY 1984; 41:99-126. [PMID: 6487222 DOI: 10.1016/s0163-1047(84)90485-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In Experiment 1, Sprague-Dawley rat pups at postnatal days 3-4, 7-8, 10-11, 15-16, and 23-24 were tested for suckling behavior on their anesthesized multiparous dams following administration of metergoline or scopolamine. The serotonergic antagonist, metergoline, inhibited suckling in 3- to 4- and 7- to 8-day-old rat pups, but was not found to influence suckling in older pups. Scopolamine, a cholinergic antagonist, reduced suckling primarily in 3- to 4-day-old pups. In Experiment 2, parity of the maternal female was manipulated to assess whether this variable would influence suckling behavior and the effects of metergoline on suckling of weanlings. Baseline levels of suckling were reduced in 23- to 24-day-old pups of primiparous dams when compared with multiparous-derived offspring. Administration of metergoline increased the amount of time that these primiparous-derived pups spent attached to nipples, but did not influence suckling of offspring of multiparous dams, perhaps as a result of a ceiling effect on suckling behavior in these animals.
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14
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Schulz DW, Mailman RB. An improved, automated adenylate cyclase assay utilizing preparative HPLC: effects of phosphodiesterase inhibitors. J Neurochem 1984; 42:764-74. [PMID: 6319607 DOI: 10.1111/j.1471-4159.1984.tb02748.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Analysis of adenylate cyclase (ACase) activity in broken cell preparations usually involves conversion of [alpha-32P]ATP to [32P]cyclic AMP (cAMP) followed by purification of cAMP by liquid chromatographic methods. An automated, preparative reverse-phase HPLC procedure was developed that purifies cAMP rapidly and decreases variability and background. It permits the separation procedure to be validated rapidly prior to use with actual samples, and is readily adaptable for assaying guanylate cyclase, phosphodiesterases (PDE), or a variety of other related nucleotide-metabolizing enzymes. For ACase assays, 4.5% ZnSO4-10% Ba(OH)2 is added to the incubation mixture, and following centrifugation, the supernatant is injected on an HPLC apparatus fitted with a Waters Z-Module containing a 10-microns C18 reverse-phase cartridge. Using a mobile phase of 0.15 M sodium acetate-20% methanol (pH 5.0) at a flow rate of 4 ml/min, cAMP is eluted at k' greater than 1.25, whereas k' less than 0.5 for all other adenine nucleotides, permitting collection of the cAMP fraction after running the other nucleotides to waste. The method was validated by characterizing dopamine-sensitive ACase in homogenates of striatum from Sprague-Dawley rats. Basal activity (177 +/- 16 pmol/mg protein/min), the stimulation by dopamine (186 +/- 19 pmol/mg/min), the apparent Km for dopamine (5.0 +/- 1.5 microM), and expected effects of varying magnesium, EGTA, and GTP were similar to available data. However, it was found that isobutylmethylxanthine (IBMX) or theophylline, usually included in the incubation mixture as PDE inhibitors, markedly inhibited the synthesis of cAMP in both the presence and absence of dopamine. A consequence of this inhibition was a marked change in the apparent Km of dopamine calculated from a Lineweaver-Burk plot. The use of IBMX to inhibit PDEs was compared with an alternate strategy, the addition of excess exogenous cAMP. Simultaneous analysis of PDE and ACase activity was accomplished by including [3H]cAMP in the incubation and quantifying the amounts of [3H]cAMP hydrolyzed and [32P]cAMP synthesized. Without IBMX, a concentration of 1 mM exogenous cAMP was sufficient to prevent significant loss of [3H]cAMP. In the absence of exogenous cAMP, 0.5 mM IBMX did not completely prevent the breakdown of [3H]cAMP, whereas 2.5 mM IBMX did. Although there was 25% less [3H]cAMP recovered in the presence of 0.5 mM IBMX than with 2.5 mM IBMX, there was no difference in the amount of [32P]cAMP formed (either with or without dopamine).(ABSTRACT TRUNCATED AT 400 WORDS)
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15
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Feigenbaum JJ, Yanai J. Normal and abnormal determinants of dopamine receptor ontogeny in the central nervous system. Prog Neurobiol 1984; 23:191-225. [PMID: 6240665 DOI: 10.1016/0301-0082(84)90002-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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16
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17
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Lamberts R, Wuttke W. Puberty of female rats may in part be explained by decreased hypothalamic dopamine receptor sensitivity. Brain Res 1981; 215:375-81. [PMID: 6790125 DOI: 10.1016/0006-8993(81)90520-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Dopamine (DA)-stimulated adenylate cyclase activity in the hypothalamus and preoptic area is highest at day 20 after birth and declines gradually to reach adult values at the time of puberty. Previously it was shown that serum prolactin levels and hypothalamic DA turnover show an inverse pattern. It is suggested that increasing prolactin levels stimulate DA turnover which results in inhibition of luteinizing hormone (LH) release. The constantly high DA turnover at later prepuberal ages desensitizes DA receptors which gradually relieves the inhibitory action of DA on LH release.
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18
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Abstract
Three day old Sprague-Dawley rat pups were placed in an incubator at room temperature (22 +/- 1 degrees C) or nest temperature (35 +/- 1.5 degrees C) and observed using a behavioral-time sampling procedure following injection of saline or quipazine (1, 2.5, 5, 10 mg/kg). Quipazine administration induced a marked behavioral activation that was characterized by increases in forward locomotion, wall climbing, forelimb paddling and hindlimb treading, the magnitudes of which were not dependent upon ambient temperature. In a second experiment, quipazine was also observed to induce mouthing behavior that was dependent upon the length of the mother-pup separation interval. These results suggests that administration of a serotonergic agonist can have marked behavioral effects in the neonatal rat pup, which reinforces previous neurochemical observations that have indicated the presence of ample postsynaptic serotonin substrates in neonatal rats. Possible implications of these results are discussed.
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19
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Church GA, Kimelberg HK, Sapirstein VS. Stimulation of carbonic anhydrase activity and phosphorylation in primary astroglial cultures by norepinephrine. J Neurochem 1980; 34:873-9. [PMID: 6766986 DOI: 10.1111/j.1471-4159.1980.tb09660.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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20
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Age-Related Changes in Neuronal and Glial Enzyme Activities. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/b978-0-12-008301-5.50011-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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21
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Walton KG, Miller E, Baldessarini RJ. Prenatal and early postnatal beta-adrenergic receptor-mediated increase of cyclic AMP in slices of rat brain. Brain Res 1979; 177:515-22. [PMID: 91411 DOI: 10.1016/0006-8993(79)90468-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The levels of cyclic AMP in slices of cerebral cortex and cerebellum from newborn rats were significantly, but transiently, increased by exposure to the beta-adrenergic agonist, isoproterenol. Isobutylmethyxanthine, an inhibitor of phosphodiesterase, enhanced this effect and permitted its detection in cerebral cortex obtained from the prenatal rat. These results are consistent with the possibilities that functional noradrenergic synapses are formed early in the ontogeny of the CNS, and that norepinephrine may exert cyclic AMP-mediated influences on brain development.
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22
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Robberecht P, Deschodt-Lanckman M, De Neef P, Christophe J. Vasoactive intestinal peptide: levels and functional receptors in rat brain before and after weaning. Life Sci 1979; 25:1001-8. [PMID: 229366 DOI: 10.1016/0024-3205(79)90584-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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23
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Bodnaryk RP. Basal, dopamine- and octopamine-stimulated adenylate cyclase activity in the brain of the moth, M amestra configurat A, during its metamorphosis. J Neurochem 1979; 33:275-82. [PMID: 379279 DOI: 10.1111/j.1471-4159.1979.tb11729.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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24
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Daszuta A, Pons F, Cadilhac J. Effect of serotonin on cyclic AMP level in rat hypothalamus slices during development. Eur J Pharmacol 1979; 56:397-401. [PMID: 225181 DOI: 10.1016/0014-2999(79)90271-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The effect of serotonin (5-HT) on cyclic AMP levels in rat hypothalamic slices was age-dependent. The sensitivity of the cyclic AMP system to 5 X 10(-5) M 5-HT already existed in the foetus at 21 days of pregnancy. It reached a maximum on the 7th postnatal day and then decreased with age. In adult tissue the response was still present and was antagonized by two serotonergic antagonists (methiothepin and metergoline). When compared to the progressive increase of 5-HT level in the hypothalamus the data suggest a different evolution of serotonergic innervation and of 5-HT receptors.
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25
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Smith TL, Hauser G. Tricyclic antidepressants and imidazolines as inhibitors of the alpha-adrenergic receptor mediated stimulation of phosphatidylinositol turnover in rat pineal gland. Biochem Pharmacol 1979; 28:1759-63. [PMID: 38796 DOI: 10.1016/0006-2952(79)90537-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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26
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Panula P, Rechardt L. Ultrastructural demonstration of adenylate cyclase activity in the rat neostriatum. Neuroscience 1979; 4:779-88. [PMID: 481749 DOI: 10.1016/0306-4522(79)90006-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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27
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Abstract
A review of the literature emphasizes that cyclic nucleotides play a key role in regulation of cell growth, differentiation and metabolism in diverse tissues and, in addition, are closely involved in neural tissue function. The role of cAMP as a second messenger is discussed.
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Affiliation(s)
- V M Wiegant
- Division of Molecular Neurobiology, Rudolf Magnus Institute for Pharmacology, Medical Faculty, University of Utrecht, The Netherlands
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28
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Roberts S, Ashby D. Ribosomal protein phosphorylation in rat cerebral cortex in vitro. Influence of cyclic adenosine 3‘:5‘-monophosphate. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)38302-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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29
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Abstract
On the basis of the information presented in this review, it is difficult to reach any firm decision regarding the role of cyclic AMP (or cyclic GMP) in synaptic transmission in the brain. While it is clear that cyclic nucleotide levels can be altered by the exposure of neural tissues to various neurotransmitters, it would be premature to claim that these nucleotides are, or are not, essential to the transmission process in the pre-or post-synaptic components of the synapse. In future experiments with cyclic AMP it will be necessary to consider more critically whether the extracellularly applied nucleotide merely provides a source of adenosine and is thus activating an extracellularly located adenosine receptor, or whether it is actually reaching the hypothetical sites at which it might act as a second messenger. The application of cyclic AMP by intrcellular injection techniques should minimize this particular problem, although possibly at the expense of new diffulties. Prio blockade of the adenosine receptor with agents such as theophylline or adenine xylofuranoside may also assist in the categorization of responses to extracellularly applied cyclic AMP as being a result either of activation of the adenosine receptor or of some other mechanism. Utimately, the developement of highly specific inhibitor for adenylate cyclase should provide a firm basis from which to draw conclusions about the role of cyclic AMP in synaptic transmission. Similar considerations apply to the action of cyclic GMP and the role of its synthesizing enzyme, guanylate cyclase. The use of phosphodiesterase inhibitors in studies on cyclic nucleotides must also be approached with caution. The diverse actions of many of these compounds, which include calcium mobilization and block of adenosine uptake, could account for many of the results that have been reported in the literature.
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30
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31
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Zimmerman ID, Berg AP. An effect of age on the phosphodiesterase activator protein of rat cerebral cortex. A brief note. Mech Ageing Dev 1977; 6:67-71. [PMID: 189141 DOI: 10.1016/0047-6374(77)90008-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Measurements were made of the effectiveness of phosphodiesterase activator protein isolated from the cerebral cortex of rats of various ages in stimulating the phosphodiesterase-catalyzed conversion of cyclic-AMP into 5'-AMP. An age dependent increase in the potency of preparations of activator protein was observed, with the activator isolated from animals six months of age and older being generally more efficacious than that from younger animals.
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32
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Coyle JT. Biochemical aspects of neurotransmission in the developing brain. INTERNATIONAL REVIEW OF NEUROBIOLOGY 1977; 20:65-103. [PMID: 22512 DOI: 10.1016/s0074-7742(08)60651-0] [Citation(s) in RCA: 129] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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33
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Baudry M, Martres MP, Schwartz JC. Modulation in the sensitivity of noradrenergic receptors in the CNS studied by the responsiveness of the cyclic AMP system. Brain Res 1976; 116:111-24. [PMID: 184881 DOI: 10.1016/0006-8993(76)90252-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Various characteristics of the altered responsiveness to noradrenaline (NA) of the cyclic Amp (cAMP) generating system of cortical brain slices have been studied in rat after chronic reserpine treatment and in mice after chronic D-amphetamine treatment. Supersensitivity of the cAMP system to NA following reserpine treatment and subsensitivity after D-amphetamine treatment exhibit many common features. Firstly, in both cases the modified responsiveness to NA occurs rapidly after the beginning of the treatment (one day for reserpine and 5 h after amphetamine) and recovers slowly after the end of the treatment. Additionally, the altered states of sensitivity of the cAMP system to NA are the result of a modification of the maximal response rather than of an altered affinity of the system to NA. Since, following D-amphetamine treatment the change of sensitivity is still apparent in the presence of a potent phosphodiesterase inhibitor, the involvement of a gross alteration of phosphodiesterase activity is unlikely. In this case too, while the response to adenosine is slightly decreased, the responses to dopamine and serotonin of the cAMP system observed in brain slices following D-amphetamine treatment is not detected in a cell-free preparation. Thus, it appears that drug treatments, modifying synaptic transmission in opposite directions, lead also to changes in opposite directions of the responsiveness of the cAMP system to NA. The hypothesis that the mechanisms underlying such phenomena are related to a modified number of functional noradrenergic receptors is discussed.
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34
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Patton MW, Nahorski SR, Rogers KJ. Regulation of cyclic adenosine 3',5'-monophosphate concentration in chick cerebral hemispheres during development. J Neurochem 1976; 27:807-12. [PMID: 184253 DOI: 10.1111/j.1471-4159.1976.tb10412.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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35
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Spano PF, Kumakura K, Govoni S, Trabucchi M. Ontogenetic development of neostriatal dopamine receptors in the rat. J Neurochem 1976; 27:621-4. [PMID: 987161 DOI: 10.1111/j.1471-4159.1976.tb12292.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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36
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Lauder JM, Krebs H. Effects of p-chlorophenylalanine on time of neuronal origin during embryogenesis in the rat. Brain Res 1976; 107:638-44. [PMID: 131603 DOI: 10.1016/0006-8993(76)90153-0] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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37
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Hungen KV, Roberts S, Hill DF. Interactions between lysergic acid diethylamide and dopamine-sensitive adenylate cyclase systems in rat brain. Brain Res 1975; 94:57-66. [PMID: 238721 DOI: 10.1016/0006-8993(75)90876-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Investigations were carried out on the interactions of the hallucinogenic drug, D-lysergic acid diethylamide (D-LSD), and other serotonin antagonists with catecholamine-sensitive adenylate cyclase systems in cell-free preparations from different regions of rat brain. In equimolar concentration, D-LSD, 2-brono-D-lysergic acid diethylamide (BOL), or methysergide (UML) strongly blocked maximal stimulation of adenylate cyclase activity by either norepinephrine or dopamine in particulate preparations from cerebral cortices of young adult rats. D-LSD also eliminated the stimulation of adenylate cyclase activity of equimolar concentrations of norepinephrine or dopamine in particulate preparations from rat hippocampus. The effects of this hallucinogenic agent on adenylate cyclase activity were most striking in particulate preparations from corpus striatum. Thus, in 10 muM concentration, D-LSD not only completely eradicated the response to 10 muM dopamine in these preparations but also consistently stimulated adenylate cyclase activity. L-LSD (80 muM) was without effect. Significant activation of striatal adenylate cyclase was produced by 0.1 muM D-LSD. Activation of striatal adenylate cyclase of either D-LSD or dopamine was strongly blocked by the dopamine-blocking agents trifluoperazine, thioridazine, chlorpromazine, and haloperidol. The stimulatory effects of D-LSD and dopamine were also inhibited by the serotonin-blocking agents, BOL, 1-methyl-D-lysergic acid diethylamide (MLD), and cyproheptadine, but not by the beta-adrenergic-blocking agent, propranolol. However, these serotonin antagonists by themselves were incapable of stimulating adenylate cyclase activity in the striatal preparations. Several other hallucinogens, which were structurally related to serotonin, were also inactive in this regard, e.g., mescaline, N,N-dimethyltryptamine, psilocin and bufotenine. Serotonin itself produced a small stimulation of adenylate cyclase activity in striatal preparations and, in relatively high concentration (100 muM), partially blocked the activation by 10 muM dopamine, but was without effect on the stimulation by 10 muM D-LSD. The present results indicate that serotonin antagonists, in general, are potent inhibitors of catecholamine-induced stimulation of adenylate cyclase systems in brain cell-free preparations. In addition, these results, coupled with earlier findings on the capacity of D-LSD to interact with serotonin-sensitive adenylate cyclase systems from rat brain23,24 and other neural systems16, strongly suggest that this hallucinogenic agent is capable of acting as an agonist at central dopamine and serotonin receptors, as well as functioning as an antagonist at dopamine, norepinephrine, and serotonin receptors in the brain.
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38
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Duffy MJ, Powell D. Stimulation of brain adenylate cyclase activity by the undecapeptide substance P and its modulation by the calcium ion. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 385:275-80. [PMID: 1125264 DOI: 10.1016/0304-4165(75)90355-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Synthetic substance P stimulated adenylate cyclase activity in particulate preparations from rat and human brain. The concentration of substance P for half maximal stimulation in rat brain was 1.8-10-minus 7 M. The stimulatory effect of substance P on the rat brain adenylate cyclase activity was 88% compared with 48% by noradrenalin, 163% by prostaglandin E1 and 184% by prostaglandin E2. Both the basal and substance P-stimulated adenylate cyclase activity in rat brain were inhibited by concentration of Ca-2+ above 10-minus 6 M. The chelating agent ethyleneglycol-bis-(beta-aminoethylether)-N, N'-tetraacetic acid at a concentration of 0.1 mM reduced the basal adenylate cyclase activity by 64% and eliminated the substance P-stimulated activity. The inhibition by ethyleneglycol-bis-(beta-aminoethylether)-N, N'-tetraacetic acid was completely reversed by increasing concentrations of Ca-2+.
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40
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Abstract
Cell-free preparations from superior and inferior colliculi of very young rats (1-3 days old) contained adenylate cyclase systems which were highly responsive to serotonin. The response to serotonin declined markedly during early development and was very low at maturity. Adenylate cyclase activity in the 10,000 times g particulate fraction from colliculi of newborn rats was significantly stimulated by 0.05 muM serotonin. Half-maximal activation was produced with less than 1 muM serotonin. Maximal stimulation of collicular adenylate cyclase was about 80% above basal enzyme activity and occurred with approximately 50 muM serotonin. Tryptamine and several derivatives of serotonin produced responses which were comparable to that obtained with serotonin; 5-methoxytryptamine was uniformly the most active compound tested. Norepinephrine or dopamine produced much smaller increases in adenylate cyclase activity. Stimulation of collicular adenylate cyclase by serotonin was significantly but incompletely blocked by serotonin antagonists, including d-lysergic acid diethylamide (d-LSD), 2-bromo-d-lysergic acid diethylamide, methysergide, 1-methyl-8 beta-carbobenzyloxy-aminomethyl-10 alpha-ergoline and cyproheptadine. Chlorpromazine also produced partial blockade. In contrast, l-lysergic acid diethylamide, haloperidol, propranolol, phenoxybenzamine and morphine were ineffective as serotonin blocking agents. Of the compounds which produced a partial blockage of serotonin action, d-LSD, cyproheptadine and chlorpromazine were themselves capable of stimulating adenylate cyclase activity. These results are consisent with the existence of multiple receptors in rat brain which are capable of interacting with indoleamines.
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41
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Guyenet PG, Beaujouan JC, Glowinski J. Ontogenesis of neostriatal cholinergic neurones in the rat and development of their sensitivity to neuroleptic drugs. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1975; 288:329-34. [PMID: 1161052 DOI: 10.1007/bf00500539] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Simultaneous determinations of the striatal contents in acetylcholine (ACh), choline acetyl-transferase (ChAc) and acetyl-cholinesterase (AChE) were made in neonate rats from day 4 to day 16 after birth. While, during this period, ChAc and AChE increased 14 and 5-fold, respectively, the change of ACh levels was smaller and more gradual. ACh levels were unaltered following the injection of thioproperazine (5 mg/kg) until day 8, then within 6 days the cholinergic neurones developed a full sensitivity to this drug. The sensitivity to haloperidol (4 mg/kg), pimozide (4 mg/kg) and to the dopamine receptor stimulating drug apomorphine (10 mg/kg) appeared along with that to thioproperazine. These data confirm and extend previous reports that rat striatal cholinergic neurones are immature at birth; they suggest, in addition, that the development of dopamine receptors occurs prior to the appearance of functional cholinergic synapses or concomitant with this event.
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42
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Von Hungen K, Roberts S, Hill DF. LSD as an agonist and antagonist at central dopamine receptors. Nature 1974; 252:588-9. [PMID: 4431522 DOI: 10.1038/252588a0] [Citation(s) in RCA: 86] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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