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At least 73 records · Page 4Linked to original sources
PubMed2006

UV tanning advertisements in high school newspapers.

OBJECTIVE: To examine the increasing use of UV tanning parlors by adolescents, despite the World Health Organization recommendation that no one under the age of 18 years use UV tanning devices. DESIGN: We examined tanning advertisements in a sample of public high school newspapers published between 2001 and 2005 in 3 Colorado counties encompassing the Denver metropolitan area. RESULTS: Tanning advertisements appeared in newspapers from 11 (48%) of 23 schools. Newspaper issues (N = 131) contained 40 advertisements placed by 18 tanning parlors. Advertisements commonly offered discounts (19 of 40) including unlimited tanning offers (15 of 40). Thirteen advertisements featured non-UV tanning treatments, and 2 advertisements mentioned parental consent or accompaniment for UV tanning. CONCLUSIONS: UV radiation, a classified carcinogen, is commonly and specifically marketed to adolescents through high school newspaper advertising. Public health skin cancer prevention policies should include the prohibition of UV tanning advertising to minors.

Adolescent↗
PubMed2004

Characteristics associated with use or intention to use indoor tanning among adolescents.

BACKGROUND: Indoor tanning is a popular behavior that may increase skin cancer risk. OBJECTIVE: To examine characteristics associated with use or intention to use indoor tanning among adolescents. METHODS: A telephone interview was conducted with 1273 adolescents, aged 14 to 17 years, in the Minneapolis-St Paul, Minn, and Boston, Mass, metropolitan areas. Questions included demographic and phenotypic characteristics, knowledge, attitudes, social factors, use of indoor tanning, and intention to tan indoors. RESULTS: Twelve percent of boys and 42% of girls had tanned indoors. Among nontanners, 22.4% planned to start, and 77.2% of tanners planned to continue tanning indoors. Nontanners and tanners at risk for future indoor tanning use were each significantly more likely to be female, less likely to use sun protection, less knowledgeable about skin cancer risks, more likely to agree that tans were attractive, and more strongly influenced by social factors compared with their low-risk counterparts. CONCLUSIONS: Our data suggest that intention to tan indoors may identify a group of adolescents at risk for adopting the behavior; prospective studies are needed for confirmation.

Adolescent↗
PubMed2006

Heterotrophic bacterial production on solid fish waste: TAN and nitrate as nitrogen source under practical RAS conditions.

The drumfilter effluent from a recirculation aquaculture system (RAS) can be used as substrate for heterotrophic bacteria production. This biomass can be re-used as aquatic feed. RAS effluents are rich in nitrate and low in total ammonia nitrogen (TAN). This might result in 20% lower bacteria yields, because nitrate conversion into bacteria is less energy efficient than TAN conversion. In this study the influence of TAN concentrations (1, 12, 98, 193, 257mgTAN/l) and stable nitrate-N concentrations (174+/-29mg/l) on bacteria yields and nitrogen conversions was investigated in a RAS under practical conditions. The effluent slurry was supplemented with 1.7gC/l sodium acetate, due to carbon deficiency, and was converted continuously in a suspended bacteria growth reactor (hydraulic retention time 6h). TAN utilization did not result in significantly different observed yields than nitrate (0.24-0.32gVSS/gC, p=0.763). However, TAN was preferred compared to nitrate and was converted to nearly 100%, independently of TAN concentrations. TAN and nitrate conversions rates were differing significantly for increasing TAN levels (p<0.000 and p=0.012), and were negatively correlated. It seems, therefore, equally possible to supply the nitrogenous substrate for bacteria conversion as nitrate and not as TAN. The bacteria reactor can, as a result, be integrated into an existing RAS as end of pipe treatment.

Ammonia↗
PubMed2005

Indoor tanning by adolescents: prevalence, practices and policies.

Despite known acute and chronic health effects from the use of indoor tanning, including the potential for all forms of skin cancer, the practice is popular in the United States (US) and Europe. A review of the scientific literature that examines adolescents and indoor tanning use was undertaken, summarising what is known about prevalence and practices among adolescents, characteristics associated with adolescent use, and policies that regulate adolescent access to indoor tanning facilities. The prevalence of indoor tanning is consistently found to be higher among girls than boys and to increase with age in both Europe and the US. An examination of other demographic characteristics, skin cancer risk factors, knowledge, attitudes and social factors points to higher prevalence of the behaviour among adolescents with positive attitudes towards tans and whose friends or parents also tan indoors. Adolescent access to indoor tanning is rarely regulated in the US or Europe, and where regulations exist, business compliance is low. In addition, businesses actively market their product to adolescents as they organise to limit further regulations prohibiting adolescent access. Pricing, licensure, advertising restrictions and media campaigns, in combination with adolescent-targeted interventions, are possible strategies that could be tested for their effectiveness to reduce adolescent indoor tanning use. Harm reduction policies, such as eye protection, that reduce risk for adolescents who choose to tan indoors, are also important.

Adolescent↗
PubMedDate not supplied

Messages influencing college women's tanning bed use: statistical versus narrative evidence format and a self-assessment to increase perceived susceptibility.

Understanding the effect of messages and other influences on health decision-making has the potential to decrease risky behavior such as tanning bed use. This study explores the effect of type of evidence, self-assessments of risk for skin cancer, and personality factors on intention to use and use of tanning beds among Caucasian female college students. Specifically, it targeted the perceived susceptibility component of the Health Belief Model and its impact on intention to tan as well as changes in actual tanning behavior. College students (N=141) in the southeast United States read randomly assigned messages and self-assessments, filled out surveys, and were later contacted for a follow-up telephone survey. The statistical message was rated higher on information value and also resulted in decreased intention to tan, decreased tanning behavior, and increased perceived susceptibility to skin cancer. The narrative message, in contrast, increased perceptions of realism and also worked to decrease intentions to tan. Additionally, the self-assessment manipulation resulted in increased susceptibility and decreased intention to tan and post tanning behavior. Personality factors explained small portions of variance. Key limitations and directions for future research are also addressed.

Adult↗
PubMed2002

Inoculum sources of the tan spot fungus Pyrenophora tritici-repentis in The Netherlands.

Since 1994 the importance of tan spot of wheat has increased in the wheat growing areas of the Netherlands. The purpose of the present study was to determine inoculum sources of this disease caused by Pyrenophora tritici-repentis. Both in 1999 and 2000, the incidence of tan spot was assessed in 40 commercial fields of winter wheat scattered over the main wheat growing areas of the Netherlands. Adjoining fields were checked for presence of stubble or crops with straw covers and the surrounding vegetation was searched for grasses with leaf spots. Straw and affected leaves of wheat and grasses were examined for P. tritici-repentis. In greenhouse experiments the pathogenicity of isolates from alternative hosts was compared with that of isolates from wheat. The possible development of P. tritici-repentis perithecia on straw of crops other than wheat was explored for barley, oat, rye grass and rape grown in fields nearby a tan spot affected wheat field. Furthermore, dispersal of tan spot was studied in a field trial in which winter wheat was sown leeward to stubble of above-mentioned severely tan spot affected wheat crop. During the surveys three cases were found of wheat crops adjoining fields with P. tritici-repentis infested stubble or straw covers. It was only after flowering that the first symptoms of tan spot appeared in the three commercial wheat crops. Couch grass (Elymus repens) was often found as host of P. tritici-repentis. In the surroundings of more then half of the wheat crops affected by tan spot this weed was also infected. Pyrenophora tritici-repentis isolates from couch grass were found to be as pathogenic to wheat as isolates from wheat to both wheat and couch grass. The observations on straw of barley, oat, rye grass, rape and wheat revealed P. tritici-repentis perithecia only on wheat straw. In the field trial with wheat sown leeward to P. tritici-repentis infested stubble, first symptoms of tan spot appeared on wheat during April and May when the release of ascospores was at a maximum. Disease severity gradually decreased with increasing distance from the side adjoining the stubble. The results of this study indicate that straw covers and stubble from tan spot diseased wheat crops and cough grass are inoculum sources of P. tritici-repentis.

Ascomycota↗
PubMedDate not supplied

Direct and indirect stimulation of megakaryocytopoiesis by TAN-1511 A, a microbial lipopeptide.

TAN-1511 A, a microbial lipopeptide, stimulates granulocytopoiesis through the induction of various hematopoietic cytokines. The ability of synthetic TAN-1511 A to affect megakaryocytopoiesis was examined. TAN-1511. A augmented the activity of acetylcholine esterase (AChE), which is a cell-lineage marker enzyme of megakaryocytes in cultured murine bone marrow cells and enhanced megakaryocyte colony formation in fibrin clot culture. These effects were observed not only in the presence, but also in the absence of IL-3, which is a megakaryocyte colony-stimulating factor. The increase in AChE activity mediated by TAN-1511 A was blocked by anti-IL-6 but not anti-IL-3 or anti-GM-CSF neutralizing antibodies. RT-PCR analysis also showed that the remarkable induction of IL-6 was triggered by treatment with TAN-1511 A, while each message level of c-mpl ligand and c-mpl remained unchanged, suggesting that the IL-6 induced by the lipopeptide plays a role in enhanced megakaryocytopoiesis. TAN-1511 A also stimulated the proliferation of CMK86, a human megakaryoblastic cell line. This promoted growth was partially and additively affected by anti-IL-3, anti-IL-6, and anti-GM-CSF antibodies. TAN-1511 A slightly reduced the expression of GpIb and GpIIb/IL1a in CMK86 cells. The enhanced platelet recovery mediated by TAN-1511 A was also demonstrated in a model of myelosuppressive mice. These results suggest that TAN-1511 A directly affects megakaryocytopoiesis, and indirectly modulates megakaryocytopoiesis through the induction of cytokines such as IL-6.

Acetylcholinesterase↗
PubMed2005

Compliance with youth access regulations for indoor UV tanning.

OBJECTIVES: To describe youth access to indoor UV tanning and youth discount pricing incentives in 4 states with different age restrictions: Colorado (no age restrictions), Texas (age 13 years), Illinois (age 14 years), and Wisconsin (age 16 years). DESIGN: Cross-sectional telephone survey conducted in October 2003 using a standardized script to assess the practices of randomly selected UV tanning operators. PARTICIPANTS: Randomly selected licensed indoor UV tanning facility operators in Colorado, Texas, Illinois, and Wisconsin. MAIN OUTCOME MEASURES: Number of facilities (1) complying with indoor UV tanning minimum age regulations for a 12-year-old potential patron and a 15-year-old potential patron and (2) offering youth discounts. RESULTS: For a 12-year-old potential patron, 62% of facilities in states with minimum age restrictions prohibiting 12-year-olds had an operator report that they would not permit indoor tanning (Texas, 23%; Illinois, 74%; and Wisconsin, 89%) compared with 18% in Colorado, a state without youth access regulations. For a 15-year-old patron, most facilities in Wisconsin, the only state with a minimum age restriction for 15-year-olds, prohibited access (77%). Overall, 15% of operators offered youth discounts: Texas, 23%; Illinois, 14%; Wisconsin, 11%; and Colorado, 11%. CONCLUSIONS: Tanning facilities in 4 states offered price incentives directed at youths. State youth access regulations were associated with decreased youth access to indoor tanning. High compliance levels in states with long-standing youth access regulations (Illinois and Wisconsin) demonstrate the potential for successful tanning industry youth access regulation.

Adolescent↗
PubMed2005

A case for informed consent? Indoor UV tanning facility operator's provision of health risks information (United States).

OBJECTIVE: Indoor UV tanning is associated with skin cancer. This study describes consumer health risks information provided by indoor UV tanning facility operators in four states (Colorado, Illinois, Texas, and Wisconsin) with varying operator training, regulations, enforcement and penalties. METHODS: Using a cross-sectional survey study design, 100 randomly selected licensed indoor UV tanning facilities from each state were surveyed anonymously by telephone. Facility operators were questioned regarding the provision of information on potential adverse effects of indoor UV exposure. RESULTS: Of 628 licensed indoor UV tanning facilities contacted, 400 facilities were surveyed. Most (87%) advised patrons of the potential risk of sunburn from indoor tanning. Less than half of facility operators in Colorado, Texas and Wisconsin informed patrons about the risk of skin cancer (42, 43 and 48%, respectively) compared with 81% of Illinois operators. Likewise, more operators in Illinois reported the risk of premature aging (79%) compared with other states (41% Colorado, 43% Texas and 51% Wisconsin). CONCLUSIONS: Tanning facility operators frequently misinformed patrons of indoor UV exposure risks. The provision of informed consent by indoor tanning facility operators needs improved adaptation by the tanning industry as a standard for customer service.

Aging, Premature↗
PubMed1995

Effects of a highly selective nonpeptide delta opioid receptor agonist, TAN-67, on morphine-induced antinociception in mice.

The effects of a potent and highly selective nonpeptide delta opioid receptor agonist, 2- methyl-4a alpha-(3-hydroxyphenyl)-1,2,3,4,4a,5,12,12a alpha- octahydroquinolino [2,3,3,-g] isoquinoline (TAN-67), on morphine-induced antinociception were examined using the warm-plate (51 degrees C) method. When a peptide delta 1 opioid receptor agonist, [D-Pen2, Pen5]enkephalin (DPDPE), was co-administered with i.c.v. morphine, low-dose morphine-induced antinociception was significantly increased. In contrast, i.c.v. co-administration of a peptide delta 2 opioid receptor agonist, [D-Ala2]deltorphin II (DELT), with morphine did not affect the morphine-induced antinociception. When morphine and TAN-67 were co-administered i.c.v., low-dose morphine-induced antinociception was significantly increased. Moreover, when TAN-67 and morphine were co-administered s.c., the morphine dose-response curve shifted to the left and the ED50 value of morphine decreased. These effects DPDPE and TAN-67 were antagonized by the delta opioid receptor antagonist naltrindole (NTI) and the delta 1 opioid receptor antagonist 7-benzylidenenaltrexone (BNTX) not by the delta 2 opioid receptor antagonist naltriben (NTB). Moreover, the mu opioid receptor antagonist beta-FNA also antagonized the effects of DPDPE and TAN-67. These results suggest that the effect of TAN-67 may result from the activation of central delta 1 opioid receptors, since the effect of TAN-67 was antagonized by NTI and BNTX, but not NTB. Furthermore, since pretreatment with beta-FNA also antagonized the effects of both DPDPE and TAN-67, a beta-FNA-sensitive site, i.e. a mu-delta complex site, may play an important role in the modulation of morphine-induced antinociception.

Analgesics↗
PubMed1995

Mutation spectra in Salmonella of sunlight, white fluorescent light, and light from tanning salon beds: induction of tandem mutations and role of DNA repair.

We evaluated the mutagenicity of sunlight (SUN), uncovered coolwhite fluorescent light (FLR), and light from a tanning salon bed (TAN) at the base-substitution allele hisG46 of Salmonella in four DNA repair backgrounds (wild type, uvrB, pKM101, and uvrB + pKM101). Approximately 80% of the radiation emitted by TAN was within the ultraviolet (UV) range, whereas only approximately 10% of the SUN and approximately 1% of the FLR radiation was UV. TAN emitted similar amounts of UVA and UVB, whereas SUN emitted 50-60x and FLR emitted 5-10x more UVA relative to UVB. Based on total dose (UV + visible), the mutagenic potency ranking was TAN > FLR > SUN. Using colony probe hybridization and PCR/DNA sequence analysis, approximately 3000 revertants were analyzed to determine the mutational specificity of the three light sources. The mutation spectra and those induced by 254-nm UV had common features. The uvrB mutation enhanced the mutagenicity of the environmental UV sources more (20-216x) than did the pKM101 plasmid (approximately 20x) relative to wild type DNA repair. All light sources induced equal proportions of transitions and transversions in excision repair-proficient strains, but they induced more transitions relative to transversions in uvrB-containing strains. The majority of the mutations were G.C-->A.T transitions that were induced equally frequently at the first or second position of the CCC codon of the hisG46 allele in all strains except TA1535 (uvrB), where SUN and FLR induced transitions preferentially at the first position, and TAN induced them preferentially at the second position. Identified or presumptive multiple mutations, which constituted the only mutational class enhanced by all three light sources in the presence of uvrB and pKM101 either alone or together, accounted for 3-5% of the induced mutations in the plasmid-containing strains, and their increases (38-82-fold) in TA100 (uvrB, pKM101) were the highest of any mutational class. Of the TAN-induced multiple mutations, 83% (19/23) were CC-->TT tandem transitions. These results show that exposures to the nonsolar environmental UV sources FLR and TAN produce mutations similar to those produced by SUN, a known carcinogen.

Alleles↗
PubMed2006

Ultrasonic effects on titanium tanning of leather.

The effects of ultrasound on titanium tanning of leather were investigated. Either 20 or 40 kHz ultrasound was applied to the titanium tanning of pigskins. Five different treatment conditions were carried out and the effects were examined, such as leather shrinkage temperature (T(s)), titanium content and titanium distribution in the leather. Overall heat loading was carefully controlled. Results showed that 20 kHz ultrasound effectively improves titanium agent penetration into the hide and increases the leather's shrinkage temperature. Doubling the frequency to 40 kHz produced negligible enhancements. An impressive 105.6 degrees C T(s) was achieved using 20 kHz ultrasound pretreatment of the tanning liquor followed by 20 kHz ultrasound in the tanning mixture (liquor plus pigskins) in a special salt-free medium. Finally, using a unique ultrasonic tanning drum with 26.5 kHz ultrasound, the T(s) reached a record level of 106.5 degrees C, a value not achieved in conventional (no ultrasound) titanium tanning. The ultrasonic effects on titanium tanning of leather are judged to make a superior mineral tanned leather.

Journal Article↗
PubMed2004

Tanning devices--fast track to skin cancer?

The use of UVB and/or UVA emitting devices for cosmetic tanning is widespread in Western populations including young people and is especially prevalent in females. Several epidemiological studies, although not all, have shown a significant relationship between the use of tanning devices and malignant melanoma after, in some cases, adjustment for confounding factors such as solar ultraviolet radiation (UVR) exposure. A relationship between solar exposure, especially intermittent exposure, and malignant melanoma is well established so it is not surprising that a similar connection has been reported for the use of tanning devices. Several epidemiological studies show that childhood exposure to sunlight is a risk factor for malignant melanoma and this may also be the case for the use of tanning devices, especially if sunburns are obtained. Some studies have evaluated the relationship between the use of tanning devices and non-melanoma skin cancer and at least one has suggested an association. The use of tanning devices by a substantial minority of young people is a worrying trend in terms of a likely increased incidence of malignant melanoma, and possibly non-melanoma cancers in the future. Although two recent reviews by epidemiologists conclude that a clear link between tanning devices and malignant melanoma is yet to be proven, there is a strong case for effective legislation to prohibit the use of tanning devices by people under 18 yr of age.

Beauty Culture↗
PubMed1977

Role of ecdysone, pupariation factors, and cyclic AMP in formation and tanning of the puparium of the fleshfly Sarcophaga bullata.

Two pupariation factors, anterior retraction factor (ARF) and puparium tanning factor (PTF), are absent from the hemolymph of larvae at the time of tanning accelerated by ARF/PTF, cyclic AMP, or dopamine. ARF and PTF are not involved in derepression of dopa decarboxylase (aromatic L-amino-acid decarboxylase, aromatic L-amino-acid carboxy-lyase, EC 4.1.1.28) synthesis initiated by ecdysone. Tanning is entirely inhibited by injection of two transcriptional inhibitors, actinomycin and BrdUrd, and two translational inhibitors, puromycin and cycloheximide. Retraction activity is more severely inhibited by the transcriptional than by the translational inhibitors. A tanning response is initiated by cyclic AMP in the presence of the transcriptional but not the translational inhibitors. Dihydric tanning substances (dopa, dopamine) initiate tanning in the presence of both types of inhibitors. Release of ARF and PTF from the central nervous system is inhibited by the four inhibitors. ARF totally reverses the inhibitory effects on retraction, whereas PTF does not reverse inhibition of tanning. These data are interpreted to mean that PTF is concerned with the regulation of two components of the tanning response: (i) acceleration of synthesis of a particular protein (associated with the tyrosine hydroxylation complex), and (ii) activation via cyclic AMP of a component of the tyrosine hydroxylating system.

Journal Article↗
PubMed2004

Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density.

BACKGROUND: Vitamin D is made in the skin on exposure to solar radiation, and it is necessary to optimal skeletal health. Subjects who use a tanning bed that emits ultraviolet B radiation (290-315 nm) are likely to have higher 25-hydroxyvitamin D [25(OH)D] concentrations than do subjects who do not regularly use a tanning bed. OBJECTIVE: The first objective of this study was to ascertain whether subjects who regularly use a tanning bed have higher 25(OH)D concentrations than do subjects who do not use a tanning bed. The second objective was to ascertain whether higher 25(OH)D concentrations correlated positively with bone mineral density. DESIGN: This cross-sectional analysis examined 50 subjects who used a tanning bed at least once a week and 106 control subjects. Each subject gave a blood specimen for measurement of serum 25(OH)D and parathyroid hormone concentrations. Each subject underwent bone mineral density testing of the hip and spine. RESULTS: Subjects who used a tanning bed had serum 25(OH)D concentrations 90% higher than those of control subjects (115.5 +/- 8.0 and 60.3 +/- 3.0 nmol/L, respectively; P <0.001). Subjects who used a tanning bed had parathyroid hormone concentrations 18% lower than those of control subjects (21.4 +/- 1.0 and 25.3 +/- 0.8 pg/mL, respectively; P=0.01). Tanners had significantly higher BMD and z scores at the total hip than did nontanners. CONCLUSION: The regular use of a tanning bed that emits vitamin D-producing ultraviolet radiation is associated with higher 25(OH)D concentrations and thus may have a benefit for the skeleton.

Absorptiometry, Photon↗
PubMed2000

Modeling tanning salon behavioral tendencies using appearance motivation, self-monitoring and the theory of planned behavior.

The constructs of appearance motivation and self-monitoring were added to the Theory of Planned Behavior in the prediction of tanning salon use in young people. The variables of the Theory of Planned Behavior proved effective at predicting tanning salon behavioral intentions and tendencies. Intentions and perceived behavioral control predicted tanning salon behavioral tendencies, while attitudes, subjective norms and perceived behavioral control predicted tanning salon behavioral intentions. Appearance motivation did not show any direct or interaction effects in the prediction of tanning salon behavioral intentions. It did, however, prove superior to health orientation in the prediction of tanning salon attitudes. Self-monitoring interacted with subjective norms in the prediction of tanning salon intentions, with high self-monitors showing stronger subjective norm-intention relationships than low self-monitors. These results imply that appearance-related interventions could prove efficacious in reducing young people's tanning salon behavioral tendencies. Furthermore, it may be important to consider individual's self-monitoring status when targeting skin cancer prevention information to young people.

Adolescent↗
PubMed1997

Factors that influence health risk behaviors among tanning salon patrons.

A principal components analysis identified the immediate convenience of indoor tanning (i.e., relaxation, perceived attractiveness of tans) as a major factor that motivates people to visit commercial tanning salons frequently and continually. Long-term considerations, such as price, socializing, and perceived health, also emerged as a motivating factor that was related to tanning frequency. Furthermore, almost half of the participants mentioned that regulations restricting indoor tanning would not make them more cautious in their tanning behavior. Findings confirm several other studies indicating that knowledge of the danger of UV exposure may have little influence on actual tanning behavior. Suggestions for alternative approaches that focus on the perceived attractiveness of tanned skin rather than the susceptibility of frequent tanners to skin cancer are discussed.

Adolescent↗
PubMed1991

Synthesis and biological activity of (S)-2-amino-3-(2,5-dihydro-5-oxo-4-isoxazolyl)propanoic acid (TAN-950 A) derivatives.

(S)-2-Amino-3-(2,5-dihydro-5-oxo-4-isoxazolyl)propanoic acid (TAN-950 A (1)) is a novel amino acid antibiotic which shows a high affinity for glutamate receptors of the central nervous system. To improve the affinity for glutamate receptors, the structure-activity relationships of TAN-950 A derivatives 6a--o, 15a--o were investigated. Optically active TAN-950 A analogs 15a--h were synthesized starting with methyl (S)- and (R)-N-Boc-pyroglutamate (8) via acylation at the C-4 position followed by isoxazolone formation with hydroxylamine and subsequent deprotection reactions. The lactam 16, prepared from (RS)-aminoadipic acid, and dimethyl esters 19 of (R)- and (S)-aspartic acid were converted to (RS)-3-methyl-homo-TAN-950 A (15i) and optically active nor-TAN-950 A derivatives 15j--o, respectively, utilizing a similar sequence of reactions. Most of TAN-950 A derivatives 6a--o, 15a--o showed an affinity for glutamate receptors. The 3-alkyl derivatives 15b, d--g, especially, showed a high affinity for the quisqualate subtype-receptor and had a strong activating effect on the hippocampal neurons (glutamate agonistic activity). The (R)-enantiomer 15a of TAN-950 A had increased selectivity for the N-methyl-D-aspartate (NMDA) subtype-receptor. This selectivity was further enhanced by removal of the methylene group in the amino acid moiety of 15a. The most potent and selective NMDA agonistic activity was observed with (R)-3-methyl-nor-TAN-950 A (15m).

Animals↗