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S J Peroutka

Publications and source records attributed to S J Peroutka.

At least 37 records · Page 2Linked to original sources
PubMed1996

5-Hydroxytryptamine receptor subtype messenger RNAs in rat peripheral sensory and sympathetic ganglia: a polymerase chain reaction study.

While serotonin has been shown to play an important role in peripheral pain mechanisms, the specific subtypes of receptors involved and their differential distribution between the sensory and sympathetic nervous system remains poorly understood. In this study, the presence of messenger RNA for rat serotonin receptor subtypes in peripheral sensory and sympathetic ganglia was detected using the method of polymerase chain reaction. Lumbar dorsal root ganglia, superior cervical sympathetic ganglia and lumbar sympathetic ganglia were excised from anesthetized Sprague-Dawley rats. Oligonucleotide primers were chosen based on unique regions of complementary DNA sequence for each of the 12 cloned rat serotonin receptor subtypes (i.e. 5-HT1A, 5-HT1B, 5-HT1D, 5-HT1F, 5-HT2A, 5-HT2B, 5-HT2C, 5-HT3, 5-HT5A, 5-HT5B, 5-HT6 and 5-HT7) and high stringency conditions were used during polymerase chain reaction. Within lumbar dorsal root ganglia, the presence of the 5-HT1B, 5-HT1D, 5-HT2A, 5-HT2C, 5-HT3 and 5-HT7 receptor subtype messenger RNAs was detected. Within superior cervical ganglia, the presence of messenger RNA for 5-HT1A, 5-HT1B, 5-HT1D, 5-HT2A, 5-HT3, 5-HT6, and 5-HT7 receptor subtypes was detected. Lumbar sympathetic ganglia displayed banding identical to the superior cervical ganglia with the exception of the 5-HT6 receptor which was not detected in the lumbar sympathetic ganglia. The polymerase chain reaction product from each positively-detected receptor subtype was subcloned and sequenced and found to correspond to published complementary DNA sequences. Findings from this study may direct further efforts to determine the role of 5-hydroxytryptamine receptors in the peripheral nervous system.

Animals↗
PubMed1996

Exclusion of 5-HT2A and 5-HT2C receptor genes as candidate genes for migraine.

Several lines of investigation suggest that the serotonergic system may be involved in the pathogenesis of migraine. In particular, drugs which block 5-HT2 receptor subtypes appear to be effective migraine prophylactic agents. Therefore, chromosomal DNA regions overlapping the 5-HT2A (13q14-q22) and 5-HT2C(Xq22-25) receptor loci were analyzed for possible linkage to the clinical diagnosis of migraine. No evidence for linkage to either chromosomal region was found, although a small subset of migrainous families showed positive likelihood of odds (LOD) scores. However, a homogeneity (HOMOG) analysis provided no statistical evidence for locus heterogeneity. The coding region of the 5-HT2A and 5-HT2C receptor genes was also analyzed in migraine patients and unaffected controls using polmerase chain reaction and direct sequencing. No mutations were found in the deduced amino acid sequence of either receptor in the sample of migraineurs tested. These results indicate that DNA-based mutations in the 5-HT2A and 5-HT2C receptors are not generally involved in the pathogenesis of migraine.

Chromosomes, Human, Pair 13↗
PubMed1995

The third intracellular loop of the 5-hydroxytryptamine2A receptor determines effector coupling specificity.

5-Hydroxytryptamine (5-HT) receptors contain seven putative transmembrane domains and couple via different guanine nucleotide binding proteins to specific effector enzymes. Studies with other receptors identify the second and third intracellular loops or the C-terminus of the receptor as important for selective effector coupling. However, it is not known which regions of the 5-HT receptor determine effector coupling specificity. To address this question, we constructed a chimeric 5-HT receptor in which the third intracellular (i3) loop is derived from the 5-HT2A receptor, which is coupled to activation of phospholipase C, and the rest of the sequence is derived from the 5-HT1B receptor, which is coupled to inhibition of adenylyl cyclase. The chimeric receptor exhibited ligand binding properties similar to those of the 5-HT1B receptor and distinct from those of the 5-HT2A receptor. This suggests that the i3 loop is not critical for the unique pharmacology of the 5-HT1B receptor. In contrast, the chimeric receptor exhibited signaling properties similar to those of the 5-HT2A receptor and distinct from those of the 5-HT1B receptor. This indicates that the i3 loop determines the effector coupling specificity of the 5-HT2A receptor.

3T3 Cells↗
PubMed1995

5-Hydroxytryptamine-induced synovial plasma extravasation is mediated via 5-hydroxytryptamine2A receptors on sympathetic efferent terminals.

5-Hydroxytryptamine (5-HT) is known to act in peripheral tissues to produce pain and inflammation, yet the mechanisms underlying 5-HT-induced inflammation have not been well studied. The present study uses a rat knee joint model of inflammation (synovial plasma extravasation) and molecular biological techniques to determine the site of action of 5-HT and the specific 5-HT receptor subtype mediating synovial 5-HT-induced plasma extravasation. 5-HT (1 microM) stimulates synovial plasma extravasation 7-fold above base-line levels. Surgical lumbar sympathectomy, but not C-fiber depletion by neonatal capsaicin, dramatically reduces 5-HT-induced synovial plasma extravasation (P < .001), indicating that sympathetic efferents mediate this effect. Polymerase chain reaction amplification of 5-HT receptor cDNA demonstrates that 5-HT1A, 5-HT1B, 5-HT1D, 5-HT2A and 5-HT3, but not the 5-HT2C, receptor subtypes are present in lumbar sympathetic ganglia. With selective ligands for these receptor subtypes, we demonstrate that 5-HT-induced synovial plasma extravasation is mediated via the 5-HT2A receptor. These findings suggest a role for 5-HT2A antagonists in various synovial inflammatory pain states.

Animals↗
PubMed1994

The effect of systemically administered recombinant human nerve growth factor in healthy human subjects.

This phase I double-masked, randomized, placebo-controlled study evaluated the safety of single intravenous or subcutaneous doses of recombinant human nerve growth factor (rhNGF) in healthy human volunteers at doses ranging from 0.03 to 1 micrograms/kg. No life-threatening adverse events were seen at any dose. At doses above 0.1 microgram/kg, subjects reported mild to moderate muscle pain, primarily in the bulbar and truncal musculature. The duration and severity of these myalgias varied in a dose-dependent manner, and women appeared to be more susceptible than men. Intravenous rhNGF produced earlier and more pronounced systemic effects than did identical subcutaneous doses. Subjects receiving subcutaneous rhNGF noted hyperalgesia at the injection site, a local effect persisting up to 7 weeks, that also varied in a dose-dependent manner. Antibodies to NGF were not detected in any subject. These results indicate that systemically administered rhNGF exerts a characteristic and reproducible biological effect in healthy subjects at very low doses and in a dose-dependent manner.

Adolescent↗
PubMed1994

Molecular biology of serotonin (5-HT) receptors.

The hypothesis that multiple serotonin (5-hydroxytryptamine; 5-HT) receptors exist was first developed in the 1950s. However, unequivocal proof of 5-HT receptor multiplicity required the availability of molecular biological technologies. Indeed, the multiplicity of 5-HT receptor subtypes, both within and between species, has far exceeded most of the predictions that might have been made on the basis of pharmacological data. Over the past few years, and especially in 1992 and 1993, numerous "new" 5-HT receptors were reported. In this review, the extensive data generated in the past few years are summarized in an evolutionary context.

Animals↗
PubMed1994

5-Hydroxytryptamine receptors in vertebrates and invertebrates: why are there so many?

In the accompanying review article, Saudou and Hen provide a comprehensive review of 5-hydroxytryptamine (5-HT) receptors. The authors appropriately raise the question of "why are there so many 5-HT receptors"? They suggest briefly that receptor multiplicity allows 5-HT to have diverse effects in the nervous system. However, 5-HT receptor multiplicity exceeds that of other biogenic amine receptors so that other explanations might be added to their suggestion. Recently, it has been hypothesized that G protein-coupled 5-HT receptors have existed for more than 750 million years (Peroutka and Howell, 1994). Although a recent flurry of "new" 5-HT receptors have appeared in the literature, the "primordial" 5-HT receptor appears to have appeared prior to the evolution of muscarinic, dopaminergic and adrenergic receptor systems. Therefore, the fact that the primordial 5-HT receptor evolved prior to other G protein-coupled biogenic amine receptors may be the reason that so many 5-HT receptors exist today.

Animals↗
PubMed1994

Role of neurologists in the pharmaceutical industry.

Important advances in the field of clinical neuropharmacology have created an increasing demand by the pharmaceutical industry for neurologists. As recently as a decade ago, neurologists were relatively rare in the pharmaceutical industry. I describe the roles played by industrial neurologists and review both the opportunities and risks in this career path.

Clinical Competence↗
PubMed1993

An Alu sequence interrupts a human 5-hydroxytryptamine1D receptor pseudogene.

Molecular cloning studies have now identified six HTR genes encoding the biosynthesis of the structurally homologous human serotonin (5-hydroxytryptamine; 5-HT) receptors, namely 5-HTR1A, 5-HTR1B, 5-HTR1C, 5-HTR1D, 5-HTR2 and 5-HTRS31. Several of these receptors are encoded by intronless genes, and we now report the cloning of another intronless serotonergic HTR gene. This gene was cloned by a method using the polymerase chain reaction. The nucleotide sequence of this gene is most closely homologous to the 5-HTR1D gene; however, several stop codons, frame shifts and deletions are present in the coding region suggesting that this is a pseudogene which could not encode a functional receptor. Sequence analysis also revealed that the coding sequence of this pseudogene is disrupted by insertion of a 283-bp Alu repeat sequence.

Amino Acid Sequence↗
PubMed1993

5-Hydroxytryptamine receptor subtypes and the pharmacology of migraine.

Multiple 5-hydroxytryptamine (5-HT) receptors have been identified in the human nervous system. A subgroup of these receptors, designated 5-HT1 receptors, appears to be involved in the mechanism of action of acute antimigraine agents. This review summarizes data indicating that compounds with proven efficacy in the acute treatment of migraine are agonist at human 5-HT1 receptors. Further studies are cited to support two possible mechanisms of action for the efficacy of 5-HT1 agonists in treating migraine. It seems likely that a single 5-HT1 receptor subtype may be found in the near future to be the final common pathway in the mechanism of action of acute antimigraine agents.

Adenylyl Cyclases↗
PubMed1992

A single amino-acid difference confers major pharmacological variation between human and rodent 5-HT1B receptors.

Neuropsychiatric disorders such as anxiety, depression, migraine, vasospasm and epilepsy may involve different subtypes of the 5-hydroxytryptamine (5-HT) receptor. The 1B subtype, which has a unique pharmacology, was first identified in rodent brain. But a similar receptor could not be detected in human brain, suggesting the absence in man of a receptor with equivalent function. Recently a human receptor gene was isolated (designated 5-HT1B receptor, 5-HT1D beta receptor, or S12 receptor) which shares 93% identity of the deduced protein sequence with rodent 5-HT1B receptors. Although this receptor is identical to rodent 5-HT1B receptors in binding to 5-HT, it differs profoundly in binding to many drugs. Here we show that replacement of a single amino acid in the human receptor (threonine at residue 355) with a corresponding asparagine found in rodent 5-HT1B receptors renders the pharmacology of the receptors essentially identical. This demonstrates that the human gene does indeed encode a 1B receptor, which is likely to have the same biological functions as the rodent 5-HT1B receptor. In addition, these findings show that minute sequence differences between homologues of the same receptor from different species can cause large pharmacological variation. Thus, drug-receptor interactions should not be extrapolated from animal to human species without verification.

Alprenolol↗
PubMed1992

Differential radioligand binding properties of [3H]5-hydroxytryptamine and [3H]mesulergine in a clonal 5-hydroxytryptamine1C cell line.

[3H]5-Hydroxytryptamine ([3H]5-HT) and [3H]mesulergine were used to label 5-HT1C receptors expressed in NIH 3T3 mouse fibroblast cells. Using a rapid filtration assay, saturation analysis of the [3H]5-HT radioligand data indicate that the binding is biphasic. Based on computerized analysis of the data, a 2-site model of radioligand binding is significantly more consistent with the data than a one-site model (P less than 0.01). The KD values of [3H]5-HT for the 2 populations are 0.5 +/- 0.1 nM and 31 +/- 15 nM, while the Bmax values are 400 +/- 90 pmol/g protein and 3,000 +/- 600 pmol/g protein, respectively. A biphasic binding pattern is also observed with [3H]5-HT using a centrifugation assay (KD1 = 0.6 +/- 0.06 nM, KD2 = 60 +/- 10 nM; Bmax1 = 740 +/- 90 pmol/g, Bmax2 = 4,000 +/- 700 pmol/g). By contrast, saturation analysis of [3H]mesulergine binding is monophasic (KD = 4.7 +/- 0.7 nM) with a Bmax value (6,800 +/- 1,000 pmol/g protein) that is significantly greater than that obtained using [3H]5-HT (P less than 0.01). Drug competition studies confirm that both [3H]5-HT and [3H]mesulergine label at least 2 subpopulations of expressed 5-HT1C receptors in NIH 3T3 cells. 10(-4) M GTP eliminates the high affinity [3H]5-HT-labeled binding sites with minimal effect on the low affinity [3H]5-HT-labeled sites and no effect on [3H]mesulergine-labeled sites. These data demonstrate that at least 2 distinct subpopulations of 5-HT1C receptors in NIH 3T3 cells can be differentiated using radioligand binding techniques.

Animals↗
PubMed1992

Characterization of the human 5-hydroxytryptamine1B receptor.

We report the cloning of a human gene encoding the 5-hydroxytryptamine1B receptor. The receptor has the characteristics of a G-protein-linked receptor and is most homologous to the human 5-HT1D receptor. This human 5-HT receptor gene, most abundantly expressed in striatum, is localized on chromosome 6, at 6q13, and the gene encoding the 5-HT1D receptor is localized on chromosome 1. Radioligand studies indicate that the affinity of [3H]5-HT is 16 +/- 2 nM. Drug competition studies indicate that the receptor displays high affinity (i.e. less than 40 nM) for 5-HT, 5-carboxyamidotryptamine, methiothepin, and metergoline.

Amino Acid Sequence↗
PubMed1992

Molecular structural basis of ligand selectivity for 5-HT2 versus 5-HT1C cortical receptors.

A molecular structural criterion of ligand selectivity for the 5-HT2 versus 5-HT1C receptor was hypothesized on the basis of radioligand binding data. Despite the large number of compounds which have been tested at both receptors, analysis of published data led to the identification of only five agents which are greater than 10-fold selective for the 5-HT2 versus the 5-HT1C receptor. Comparison of the two-dimensional structures revealed that, although these five compounds represent three distinct structural classes, they share a common structural feature located in the region hypothesized to be involved in receptor binding: a carbonyl or carboxyl oxygen interposed spatially between an aromatic ring and nitrogen atom. This structural feature was used to predict the relative selectivity of compounds that had not previously been analyzed at both the 5-HT2 and 5-HT1C receptors. All six drugs tested which contain the identified reactive carbonyl or carboxyl group were found to be selective for the 5-HT2 versus the 5-HT1C receptor with selectivity ratios ranging from 26 to 380. By contrast, three agents which are structurally similar but do not contain the reactive carbonyl or carboxyl group displayed equally high affinity for both receptor binding sites. Since the physiological roles of the 5-HT2 and 5-HT1C receptor are markedly different, it would be of potential clinical and scientific value to utilize this molecular structural feature to further identify chemical compounds which would selectively interact with only one of the two receptors.

Animals↗
PubMed1992

Phylogenetic tree analysis of G protein-coupled 5-HT receptors: implications for receptor nomenclature.

The nomenclature system used to characterize 5-hydroxytryptamine receptor subtypes remains controversial. To date, the majority of nomenclature systems have been on the differential pharmacological properties of the receptors. However, the availability of molecular biological data allows for a nomenclature system based on the structural properties of the receptors. The evolutionary relationships between the known G protein-coupled 5-HT receptor subtypes were determined by a phylogenetic tree analysis. The data indicate that 2 major classes of G protein-coupled 5-HT receptors have evolved. Each of the 2 branches differentiate into additional 5-HT receptor subtypes. The most recent branching of 5-HT receptor subtypes occurs at the level of individual species. These data also indicate that the degree of structural similarity (e.g. 93% identify between human and rat 5-HT1B receptors) does not necessarily correlate with pharmacological similarity. Phylogenetic tree analysis allows for a nomenclature framework that can be easily expanded to incorporate additional 5-HT receptor subtypes that have yet to be identified.

Animals↗