Chronic Dopamine D1, Dopamine D2 and Combined Dopamine D1 and D2 Antagonist Treatment in Cebus Apella Monkeys: Antiamphetamine Effects and Extrapyramidal Side Effects

To determine: (1) whether the apparent lack of efficacy of dopamine D1 (D1) antagonists in the clinic might be attributable to development of tolerance to antipsychotic effects; and (2) whether combined D1 and D2 antagonism might contribute to clozapine’s clinical profile, eight Cebus apella monkeys were chronically treated with a D1 antagonist (NNC 756) ((+)-8-chloro-7-hydroxy-3-methyl-5-(7-(2,3-dihydrobenzofuranyl)-2,3,4,5-tetrahydro-1H-3-benzazepine), a D2 antagonist (raclopride) or a combination of the two antagonists. Prior neuroleptic exposure had resulted in oral dyskinesia in seven monkeys and sensitization to dystonia in all, yielding a model for acute and chronic extrapyramidal side effects (EPS). Dextroamphetamine-induced motoric unrest and stereotypies were used as a psychosis model. We found tolerance toward dystonic symptoms during D1 and D1 + D2 treatments but not during D2 treatment. D2 but not D1 or D1 + D2 antagonism caused exacerbation of dyskinesia. Both D1 and D1 + D2 antagonism were superior to D2 antagonism alone in counteracting the amphetamine-induced behaviors, with no tolerance to antiamphetamine effects. These findings suggest: (1) reasons other than tolerance (e.g., differences among antagonists) may explain the lack of efficacy in clinical trials with D1 antagonists; and (2) that D1 antagonism alone or combined and modest D1 and D2 antagonism offers the potential of antipsychotic efficacy with a lower risk of EPS than traditional D2 antagonism. Further clinical trials with D1 or combined D1 and D2 antagonists are, therefore, recommended.     

Quantitation of serum 25(OH)D2 and 25(OH)D3 concentrations by liquid chromatography tandem mass spectrometry in patients with diabetes mellitus

Vitamin D has been considered to regulate calcium and phosphorus homeostasis and to preserve skeletal integrity. Serum 25-hydroxyvitamin D (25(OH)D) is the best indicator of vitamin D levels. The association of serum 25(OH)D deficiency with increased risk of type 1 diabetes (T1DM) and type 2 diabetes (T2DM) is controversial. We investigated serum 25(OH)D₂ and 25(OH)D₃ levels in diabetes patients by using liquid chromatography tandem mass spectrometry (LC-MS/MS). Serum 25(OH)D2 and 25(OH)D3 levels were measured with liquid chromatography tandem mass spectrometry in electrospray ionization positive mode. Chromatograms were separated using an ACE5 C18 column on a gradient of methanol. The total 25(OH)D levels were calculated as the sum of 25(OH)D3 and 25(OH)D2 levels. A total of 56 patients with T1DM and 41 patients with T2DM were enrolled in this study. There were 42 and 28 non-diabetic, age-matched volunteers who participated as the T1DM controls and the T2DM controls, respectively. The total 25(OH)D levels were lowest in the 21–40 age group. The levels of both 25(OH)D3 and the total 25(OH)D were significantly higher in the T1DM and T2DM groups than in the controls (p < 0.01 in T1DM and p < 0.05 in T2DM group, respectively). The 25(OH)D2 levels were only significantly higher in T1DM patients than in the controls. The percentages of vitamin D deficiency (total 25(OH)D less than 20 ng/mL) in the T1DM, T2DM, the T1DM controls and the T2DM controls were 7.1%, 0%, 14.3% and 3.6%, respectively. The percentages of vitamin D insufficiency (total 25(OH)D less than 30 ng/mL) in the T1DM, T2DM, the T1DM controls and the T2DM controls were 26.8%, 7.3%, 54.8% and 17.9%, respectively. The percentages of vitamin D deficiency and insufficiency were significantly lower in the T1DM patients than in the T1DM controls (p < 0.01). In the present study, both type 1 and type 2 diabetes patients had higher serum 25(OH)D levels and lower percentages of vitamin D deficiency/insufficiency.     

Comparison of the relative effects of 1,24-dihydroxyvitamin D(2) [1, 24-(OH)(2)D(2)], 1,24-dihydroxyvitamin D(3) [1,24-(OH)(2)D(3)], and 1,25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] on selected vitamin D-regulated events in the rat

The present experiments were conducted to compare the relative hypercalciuric and hypercalcemic activities of 1,24-dihydroxyvitamin D(2) [1,24-(OH)(2)D(2)], 1,24-dihydroxyvitamin D(3) [1, 24-(OH)(2)D(3)], and 1,25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] in 7-week-old rats. The rats were dosed orally with each sterol for 7 days at a rate of 1 ng/g body weight/day. We also monitored the effect of the three compounds on the induction of mRNA for CaATPase and for 25-hydroxyvitamin D-24-hydroxylase in the kidney and intestine, on plasma vitamin D metabolite levels, and on the capacity to evoke modification in the vitamin D receptor/retinoic acid X receptor (VDR/RXR) heterodimer conformation. Plasma calcium was elevated in the rats treated with 1,24-(OH)(2)D(3) and 1, 25-(OH)(2)D(3), but not in the 1,24-(OH)(2)D(2)-dosed rats. Urinary calcium was elevated significantly (relative to controls) in all groups. The order of hypercalciuric activity was 1,25-(OH)(2)D(3) >/= 1,24-(OH)(2)D(3) >/= 1,24-(OH)(2)D(2) > control. Duodenal plasma membrane calcium ATPase (PMCA) mRNA was elevated to a similar extent in all groups relative to controls. Duodenal 24-hydroxylase mRNA was elevated in all groups relative to controls; however, the elevations were significantly higher in the 1,24-(OH)(2)D(3) and 1, 25-(OH)(2)D(3) groups compared with the 1,24-(OH)(2)D(2) group. Kidney 24-hydroxylase also was elevated significantly in the 1, 24-(OH)(2)D(3)- and 1,25-(OH)(2)D(3)-treated rats but not in the 1, 24-(OH)(2)D(2)-treated rats. Recombinant human vitamin D receptor (hVDR) extracts were incubated with saturating concentrations of 1, 24-(OH)(2)D(2), 1,24-(OH)(2)D(3), and 1,25-(OH)(2)D(3) and subsequently analyzed by electrophoretic mobility shift assay (EMSA). Overall binding was comparable for all metabolites; however, the 1, 24-(OH)(2)D(2) complex exhibited distinctly altered mobility relative to 1,24-(OH)(2)D(3) and 1,25-(OH)(2)D(3), suggestive of an effect on hVDR/hRXR conformation. These data suggest that 1, 24-(OH)(2)D(2) is not as potent as either of the vitamin D(3) sterols at affecting hypercalcemia or hypercalciuria in young growing rats; however, 1,24-(OH)(2)D(2) can evoke other biological responses similar to the vitamin D(3) sterols. These different responses may be related to the alterations in conformation state of the hVDR/hRXR heterodimer.     

Rapid control of transmembrane calcium influx by 1alpha,25-dihydroxyvitamin D3 and its analogues in rat osteoblast-like cells.

1alpha,25-Dihydroxyvitamin D3 [1alpha,25(OH)2D3] has been shown to exert both its nuclear vitamin D receptor (nVDR)-mediated genomic actions and membrane vitamin D receptor (mVDR)-mediated nongenomic actions. In this study, the effects of 1alpha,25(OH)2D3 and its analogues on transmembrane Ca2+ influx were examined in the growth phase of rat osteosarcoma ROS17/2.8 cells. Like BAYK8644 (2 x 10(-5)M), a well-known L-type Ca2+ channel agonist, 1alpha,25(OH)2D3 (10(-8)M) increased transmembrane influx of Ca2+ through voltage-dependent Ca2+ channels and increased intracellular Ca2+ concentration within 2 min of addition to the medium. The 1alpha,25(OH)2D3-induced Ca2+ influx was completely blocked by pre-treatment with nifedipine (2 x 10(-5)M), an L-type Ca2+ channel antagonist. Two vitamin D analogues, 22-oxa-1alpha,25(OH)2D3 (OCT, 10(-8) M) and 20-epi-22-oxa-24a, 26a,27a-trihomo-1alpha,25(OH)2D3 (KH1060, 10(-8)M), which were 3.8 and 3600-fold more active than 1alpha,25(OH)2D3 in stimulating differentiation on human promyelocytic leukemic HL-60 cells, respectively, also increased intracellular Ca2+ concentration, while their Ca2+ channeling activities were similar to or significantly weaker than that of 1alpha,25(OH)2D3. Furthermore, the enhanced transmembrane Ca2+ influx induced by 1alpha,25(OH)2D3 (10(-8)M) or OCT (10(-8)M) was completely blocked by pre-treatment with the respective 1beta epimer [1beta,25(OH)2D3 and 1beta-OCT] at equal concentration. These findings suggest that 1alpha,25(OH)2D3 and its analogues modulate transmembrane Ca2+ influx in osteoblast-like cells by opening L-type Ca2+ channels which can recognize 1alpha-hydroxy analogues as agonists and 1beta-hydroxy analogues as antagonists.     

知母中三个新的呋甾皂苷

从中药知母（ＡｎｅｍａｒｒｈｅｎａａｓｐｈｏｄｅｌｏｉｄｅｓＢｇｅ．）中分离出三种新的呋甾皂苷，初步鉴定为（２５Ｓ）－２６－Ｏ－β－Ｄ－葡萄糖－５β－呋甾－２０（２２）－双键－３β，２６－二醇－３－Ｏ－β－Ｄ－葡萄糖基（１→２）〔β－Ｄ－葡萄糖基（１→３）〕－β－Ｄ－葡萄糖基（１→４）－β－Ｄ－半乳糖苷（１），（２５Ｓ）－２６－Ｏ－β－Ｄ－葡萄糖基－２２－羟基－５β－呋甾－３β，２６－二醇－３－Ｏ－β－Ｄ－葡萄糖基（１→２）〔β－Ｄ－葡萄糖基（１→３）〕－β－Ｄ－葡萄糖基（１→４）－β－Ｄ－半乳糖苷（２），（２５Ｓ）－２６－Ｏ－β－Ｄ－葡萄糖基－２２－甲氧基－５β－呋甾－３β，２６－二醇－３－Ｏ－β－Ｄ－葡萄糖基（１→２）〔β－Ｄ－葡萄糖基（１→３）〕－β－Ｄ－葡萄糖基（１→４）－β－Ｄ－半乳糖苷（３）．分别命名为ｔｉｍｏｓａｐｏｎｉｎ－ＢⅣ，ｔｉｍｏ－ｓａｐｏｎｉｎ－ＢⅤ，ｔｉｍｏｓａｐｏｎｉｎ－ＢⅥ．     

Role of D(1) and D(2) dopamine receptors in the acquisition and expression of flavor-preference conditioning in sham-feeding rats

The present study examined the effects of D(1) and D(2) antagonists on flavor-preference conditioning by the sweet taste of sucrose. All sessions were conducted under sham-feeding conditions to minimize post-ingestive influences. The rats were trained in alternating, one-bottle sessions to sham-feed a 16% sucrose solution containing one novel flavor (CS+) and a less-preferred 0.2% saccharin solution containing a different flavor (CS-). Three groups of food-restricted rats were treated with either vehicle (control group), the D(1) antagonist, SCH23390 (200 nmol/kg), or the D(2) antagonist, raclopride (200 nmol/kg) during one-bottle training. A fourth group (yoked group) was vehicle-treated and its training intakes were matched to that of the D(1) and D(2) drug groups. Preferences were assessed in two-bottle tests with the CS+ and CS- flavors presented in mixed 8% sucrose+0.1% saccharin solutions following systemic doses of 0, 200, or 800 nmol/kg of either the D(1) or D(2) antagonists. All groups significantly preferred the CS+ flavor in vehicle tests, although the preferences were weaker in the D(1), D(2), and yoked groups compared to the control group. All groups selectively reduced their CS+ intakes when treated with either D(1) or D(2) antagonists during two-bottle testing, and the CS+ preference was blocked at the higher doses. These data show that D(1) and D(2) receptor antagonists block the expression of a sucrose-conditioned preference, but produces substantially lesser effects upon the acquisition of this form of flavor conditioning.     

trans-1-[(2-Phenylcyclopropyl)methyl]-4-arylpiperazines: mixed dopamine D(2)/D(4) receptor antagonists as potential antipsychotic agents

The dopaminergic receptor profile of a series of trans-1-[(2-phenylcyclopropyl)methyl]-4-arylpiperazines was examined. Aromatic substitution patterns were varied with the goal of identifying a compound having affinities for the D(2) and D(4) receptors in a ratio similar to that observed for the atypical neuroleptic clozapine. The compounds (1S, 2S)-trans-1-[(2-phenylcyclopropyl)methyl]-4-(2, 4-dichlorophenyl)piperazine (5m) and (1S, 2S)-trans-1-[(2-phenylcyclopropyl)methyl]-4-(2, 4-dimethylphenyl)piperazine (5t) were selected for functional antagonists at D(2) and D(4) receptors and had a D(2)/D(4) ratio approximating that of clozapine; they proved inactive in behavioral tests of antipsychotic activity.     

CYP2D6基因多态性对帕罗西汀在中国健康人药动学影响

目的研究中国健康人CYP2D6基因多态性对帕罗西汀药动学的影响。方法使用PCR-RFLP方法将23位志愿者分为3组:CYP2D6*1/*1组(n=5),CYP2D6*1/*10组(n=7),CYP2D6*10/*10组(n=11)。给予帕罗西汀20 mg单剂量口服,收集给药后96 h内的一系列血样,用LC-MS/MS法测定帕罗西汀的血药浓度并做药动学分析。结果与CYP2D6*1/*1组药动学参数相比,CYP2D6*1/*10组t_(max)、t1/2和CYP2D6*10/*10组t_(max)无显著差异(P>0.05);CYP2D6*1/*10、CYP2D6*10/*10组的ρ_(max)、AUC_(0-96 h)、AUC_(0-∞)、CL(F)、Vd和CYP2D6*10/*10组t_(1/2)均有显著差异(P<0.05或P<0.01)。结论 CYP2D6*10等位基因突变能引起代谢表型的改变,影响帕罗西汀在健康人的体内代谢。     

Relationship between Type A and B personality and debrisoquine hydroxylation capacity

AIM: A person with Type A personality is an 'aggressor' compared with the rarely harried Type B. Although debrisoquine hydroxylase (CYP2D6) capacity has been associated with personality, no study has specifically investigated its association with personality Type A and B. Therefore the aim of this research was to study the impact of CYP2D6 on Type A and B personality. METHODS: Type A and B personality questionnaires were administered to 48 healthy patients undergoing elective orthopaedic surgery. After obtaining informed consent, patients were genotyped for the various CYP2D6 alleles by allele-specific polymerase chain reaction. Based on the genotypes, patients were grouped as extensive metabolizer (EM)1 (normal) (CYP2D6*1/*1), EM2 (intermediate) (CYP2D6*1/*4, CYP2D6*1/*5, CYP2D6*1/*9 and CYP2D6*1/*10) and EM3 (slow) (CYP2D6*4/*10, CYP2D6*5/*10, CYP2D6*10/*10 and CYP2D6*10/*17). Chi(2) was used to determine the relationship between the groups and personality types. RESULTS: The percentages of patients who were of the EM1, EM2 and EM3 groups were 20.8%, 52.1% and 27.1%, respectively. There was a significant difference (P = 0.032) between the three groups in terms of personality type, in which EM1 showed a tendency to be of personality Type A while EM2 and EM3 tended to be of personality Type B. CONCLUSION: The study suggests that there is a relationship between CYP2D6 activity and Type A and B personality.     

Changes in muscle tone are regulated by D1 and D2 dopamine receptors in the ventral striatum and D1 receptors in the substantia nigra.

Muscle rigidity associated with antipsychotic drug treatment is believed to result from reduced striatal dopamine neurotransmission. In the current study the regulatory roles of dopamine D1 and D2 receptor subfamilies in the dorsal (DSTR) and ventral striatum (VSTR) and substantia nigra (SN) were investigated on muscle tone, assessed as increases in tonic electromyographic (EMG) activity. Rats were injected with the irreversible D1/D2 antagonist N-ethoxycarbonyl-2-ethoxy, -1,2-dihydroquinoline (EEDQ), the reversible D1 antagonist SCH23390, or D2 antagonist sulpiride. Increased EMG activity was observed following injection of EEDQ and SCH23390 into the SN or VSTR, and sulpiride into the VSTR. Mapping, using quantitative autoradiographic analysis of dopamine receptor occupancy after striatal injections, showed D1 and D2 receptors in discrete ventral sites were associated with EMG increases. Overall the results support roles for dopamine D1 and D2 receptors in the ventral striatum, and D1 receptors in the substantia nigra, in the regulation of muscle tone.     

Synthesis and structure-activity relationships of naphthamides as dopamine D3 receptor ligands

A series of naphthamides were synthesized, and the affinities of these compounds were determined for dopamine D2 and D3 receptors using radioligand binding techniques. The naphthamide compounds that were prepared include N-(1-alkylpiperidin-4-yl)-4-bromo-1-methoxy-2-naphthamides (1-6), (S)-N-(1-alkylpyrrolidin-3-yl)-4-bromo-1-methoxy-2-naphthamides (7-12), (R)-N-(1-alkylpyrrolidin-3-yl)-4-bromo-1-methoxy-2-naphthamides (13-18), (S)-N-(1-alkyl-2-pyrrolidinylmethyl)-4-bromo-1-methoxy-2-naphthamides (19-25), (R)-N-(1-alkyl-2-pyrrolidinylmethyl)-4-bromo-1-methoxy-2-naphthamides (26-31), and N-(9-alkyl-9-azabicyclo[3.3.1]nonan-3beta-yl)-4-bromo-1-methoxy-2-naphthamides (32, 33). The results of in vitro radioligand binding studies indicated that the majority of the naphthamide analogues bound with high affinity at both the D2 and D3 dopamine receptor subtypes and most of the compounds demonstrated some selectivity for the dopamine D3 dopamine receptor subtype. These results demonstrated that both the structure of the central amine moiety (piperidine, pyrrolidine, and 9-azabicyclo[3.3.1]nonane) ring and the N-(alkyl) substitution on the amine significantly effects the binding affinity at D2 and D3 dopamine receptors. The bulkiness of the N-(1-alkyl) substituent was found to (a) have no effect on pharmacologic selectivity, (b) increase the affinity at D3 receptors, or (c) decrease the affinity at D2 receptors. The most potent analogue in this series was (S)-N-(1-cycloheptylpyrrolidin-3-yl)-4-bromo-1-methoxy-2-naphthamide (10), which had equilibrium dissociation (K(i)) values of 1.8 and 0.2 nM for D2 and D3 receptors, respectively. The most selective analogue was (R)-N-(1-cycloheptyl-2-pyrrolidinylmethyl)-4-bromo-1-methoxy-2-naphthamide (30), which had K(i) values of 62.8 and 2.4 nM for D2 and D3 receptors, respectively. Radioligand binding results for sigma receptors indicated that the structure of the amine moiety and the N-(1-alkyl) substitutions also significantly influence the affinity and selectivity of these compounds at the sigma1 and sigma2 sigma receptor subtypes. The two naphthamides containing a 9-azabicyclo[3.3.1]nonan-3beta-yl central ring were found to be selective for sigma2 receptors.     

Phytochemical and biological investigation of Begonia heracleifolia

From the rhizomes of Begonia heracleifolia six known cucurbitacins ( 1- 6) were isolated. Based on spectral data (1D and 2D (1)H-, (13)C-NMR, ESI- and CI-MS) the structures were established as cucurbitacin B ( 1), cucurbitacin D ( 2), 23,24-dihydrocucurbitacin D ( 3), 23,24-dihydrocucurbitacin F ( 4), 2- O-beta-glucopyranosyl-cucurbitacin B ( 5), and 2- O-beta-glucopyranosyl-cucurbitacin D ( 6). Four of them ( 3- 6) were so far not reported as constituents of Begonia spp. Varyingly strong antiproliferative activity towards tumor and immune cells was observed for three compounds ( 1 - 3), due to different structural features.     

Characterization of (+/-)-bufuralol hydroxylation activities in liver microsomes of Japanese and Caucasian subjects genotyped for CYP2D6

Twenty-four genetic polymorphisms in the CYP2D6 gene were analysed in liver DNA samples of 39 Japanese and 44 Caucasians and compared with CYP2D6 protein levels and bufuralol 1'- and 6-hydroxylation activities in liver microsomes of these human samples. We detected 13 types of CYP2D6 genetic polymorphisms and classified these into 20 genotypes; nine types were found in Japanese and 14 types in Caucasian samples. CYP2D6*10B, but not CYP2D6*10A, was the most frequent (34.6%) in Japanese. In Caucasians, several CYP2D6 polymorphisms including CYP2D6*4, *4D, *4E, *4L, *3, *9, *5 and *2E (frequencies of 6.8, 3.4, 4.5, 9.1, 1.1, 2.3, 2.3 and 4.5%, respectively) were detected. A Caucasian having CYP2D6*3/*5 had a protein with slower gel mobility (immunoblotting with anti-CYP2D6 antibody) and very low activity for bufuralol 1'-hydroxylation. Five Caucasian samples (CYP2D6*4/*4, *4/*4L, or *4D/*4L) had no measurable CYP2D6 protein and very low bufuralol 1'-hydroxylation activities. Seven Japanese subjects with CYP2D6*10B/*10B had CYP2D6 protein at levels of approximately 20% of those present in humans with CYP2D6*1 and *2 and catalysed bufuralol 1'-hydroxylation at low rates. Kinetic analysis of bufuralol 1'- and 6-hydroxylation indicates that (i) the Km values for 1'-hydroxylation were lower in individuals with CYP2D6*1/*1, *1/*2, *1/*2X2, and *2/*2 than those with CYP2D6*4/*4, *4/*4L, *4D/*4L, or *10B/*10B and Vmax values tended to be higher in the former groups (*1, *2), and (ii) individuals with heterozygous CYP2D6*1/*4D, *1/*4L, and *1/*5 had relatively high Vmax/Km ratios, whereas individuals with heterozygous CYP2D6*1/*9, *2/4D, *2/*5, *2/*10B, *2E/*4E, *3/*5, *4L/*9, and *10B/*39 had lower Vmax/Km ratios for bufuralol 1'-hydroxylation. Quinidine inhibited bufuralol 1'-hydroxylation in liver microsomes, particularly at low substrate concentrations, in individuals with CYP2D6*1/*1, and 1/1*2, but not those with CYP2D6*4/*4 and very slightly in individuals with CYP2D6*10B/*10B. The latter two groups were found to be more sensitive to alpha-naphthoflavone than the former groups, indicative of the contribution of CYP1A2. These results support the view that CYP2D6*3, *4, *4D, and *4L are major genotypes producing poor metabolizer phenotypes in CYP2D6 in Caucasians, whereas CYP2D6*10B is a major factor in decreased CYP2D6 protein expression and catalytic activities in Japanese.     

Haloperidol-induced catalepsy is absent in dopamine D(2), but maintained in dopamine D(3) receptor knock-out mice

We have previously found that mice homozygous for the deletion of the dopamine D(2) receptor gene (D(2)(-/-) mice) do not present spontaneous catalepsy when tested in a "bar test". In the present study, we sought to analyse the reactivity of D(2) receptor mutant mice to the cataleptogenic effects of dopamine D(2)-like or D(1)-like receptor antagonists. In parallel, we assessed the cataleptogenic effects of these antagonists in dopamine D(3) receptor mutant mice. D(2)(-/-) mice were totally unresponsive to the cataleptogenic effects of the dopamine D(2)-like receptor antagonist haloperidol (0.125-2 mg/kg i.p.), while D(2)(+/-) mice, at the highest haloperidol doses tested, showed a level of catalepsy about half that of wild-type controls. The degree of haloperidol-induced catalepsy was thus proportional to the level of striatal dopamine D(2) receptor expression (0.50, 0.30 and 0.08 pmol/mg protein as measured at 0.25 nM [3H]spiperone for D(2)(+/+), D(2)(+/-) and D(2)(-/-) mice, respectively). However, D(2)(-/-) and D(2)(+/-) mice were as sensitive as their wild-type counterparts to the cataleptogenic effects of the dopamine D(1)-like receptor antagonist R-(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4, 5-tetrahydro-1H-3-benzazepine hydrochloride (SCH 23390: 0.03-0.6 mg/kg s.c.). Striatal dopamine D(1) receptor expression (as measured using [3H]SCH 23390 binding) was not significantly affected by the genotype. The ability of SCH 23390 to induce catalepsy in D(2)(-/-) mice suggests that their resistance to haloperidol-induced catalepsy is due to the absence of dopamine D(2) receptors, and not to the abnormal striatal synaptic plasticity that has been shown by others to occur in these mice. In agreement with the observation that dopamine D(2) and dopamine D(1) receptor expression was essentially identical in D(3)(+/+), D(3)(+/-) and D(3)(-/-) mice, dopamine D(3) receptor homozygous and heterozygous mutant mice, on the whole, did not differ from their controls in the time spent in a cataleptic position following administration of either haloperidol (0.5-2 mg/kg i.p.) or SCH 23390 (0.03-0.6 mg/kg s.c.). Also, dopamine D(3) receptor mutant mice were no more responsive than wild-type controls when co-administered subthreshold doses of haloperidol (0.125 mg/kg) and SCH 23390 (0.03 mg/kg), suggesting that dopamine D(3) receptor knock-out mice are not more sensitive than wild-types to the synergistic effects of concurrent blockade of dopamine D(2) and dopamine D(1) receptors in this model. These results suggest that the dopamine D(2) receptor subtype is necessary for haloperidol to produce catalepsy, and that the dopamine D(3) receptor subtype appears to exert no observable control over the catalepsy produced by dopamine D(2)-like, D(1)-like and the combination of D(1)-like and D(2)-like receptor antagonists.     

Conjugated enynes as nonaromatic catechol bioisosteres: synthesis, binding experiments, and computational studies of novel dopamine receptor agonists recognizing preferentially the D(3) subtype

To evaluate nonaromatic catechol bioisosteres, the conformationally restrained enynes 1 and enediynes 2 were synthesized via palladium-catalyzed coupling as the key reaction step. Subsequent receptor binding studies at the dopamine receptor subtypes D(1), D(2 long), D(2 short), D(3), and D(4) showed highly interesting binding profiles for the enynes 1a and 1b when compared to dopamine. At the guanine nucleotide-sensitive high-affinity binding site of the D(3) receptor, the target compound 1b (K(i) = 5.2 nM) was 10-fold more potent than dopamine but less potent at the D(2) and D(4) subtypes. In contrast to dopamine the agonists 1a and 1b showed strong selectivity for the receptors of the D(2) family (D(2)-D(4)). As far as we know, this study represents the first report on nonaromatic dopamine agonists. Comparison of molecular electrostatic potentials, derived from semiempirical molecular orbital calculations, and lipophilicity maps was performed.     

地佐辛联合不同剂量右美托咪定用于OSAHS患者经鼻清醒插管的效果比较

目的　观察地佐辛联合不同剂量右美托咪啶用于阻塞性睡眠呼吸低通气暂停综合征（OSAHS）患者行纤维支气管镜引导经鼻清醒气管插管（AFNI）的效果。方法　OSAHS患者80例按随机数字表法分为地佐辛0.1 mg/kg组（C组）、地佐辛0.1 mg/kg+右美托咪定（DEX）0.5 µg/kg组（D1组）,地佐辛0.1 mg/kg+DEX 1 µg/kg组（D2组）,地佐辛0.1 mg/kg+DEX 1.5 µg/kg组（D3组）,每组20例。在给予全部患者静脉注射地佐辛0.1 mg/kg的同时,C组静脉泵注0.5 µg/kg生理盐水,D1、D2、D3组分别静脉泵注DEX 0.5、1、1.5 µg/kg（10 min泵完）。气管插管前5 min行鼻腔咽喉表面麻醉,药泵注结束行AFNI。比较4组入室时（T0）、插管前（T1）和插管后（T2）心率（HR）、平均动脉压（MAP）、血氧饱和度（SPO2）、脑电双频指数（BIS）值和Ramsay镇静评分、插管耐受度、插管时间、患者对插管的满意度、气道阻塞评分及不良反应（心动过缓、呼吸抑制、躁动、对插管有记忆）的发生率。结果　时间和干预方式对HR、MAP、BIS值及Ramsay镇静评分有交互作用（P＜0.05）,对SPO2无交互作用（P＞0.05）,只有时间因素影响SPO2（P＜0.05）。组间多重比较显示,D2组在T1、T2时点HR、MAP较C组降低,在T2时点较D1组降低（P＜0.05）;D3组较C组、D1组在T1、T2时点HR、MAP降低;D3组心动过缓发生率较C组升高（P＜0.05）;与C组、D1组比较,D2、D3组在T1、T2时点的BIS值降低、Ramsay镇静评分升高,躁动和对插管有记忆的发生率降低,气管插管耐受度增强,气管插管时间缩短,插管满意度高（P＜0.05）。结论　地佐辛联合DEX可有效安全地用于OSAHS患者的AFNI,且以地佐辛0.1 mg/kg联合DEX 1 µg/kg时,既能维持患者血流动力学稳定又能减少不良反应发生率。     

Syntheses and differentiating action of vitamin D endoperoxides. Singlet oxygen adducts of vitamin D derivatives in human myeloid leukemia cells (HL-60)

Singlet oxygen adducts of various vitamin D derivatives, 6,19-dihydro-6,19-epidioxyvitamin D (vitamin D endoperoxides, 2 and 2'), were chemically synthesized, and their biological activity in inducing differentiation of a human myeloid leukemia cell line (HL-60 cells) was examined. The potency of the endoperoxides derived from vitamin D derivatives possessing the 1 alpha-hydroxyl group such as 1 alpha, 25-dihydroxyvitamin D3 endoperoxides (2b and 2b') was markedly (10(-2)) diminished relative to the respective parent vitamin D compounds. In contrast, 25-hydroxyvitamin D3 endoperoxides [25-(OH)D3 endoperoxides, 2a and 2a'] and their analogues fluorinated at the 24- or 26- and 27-positions were 2.5-10 times more potent than 25-hydroxyvitamin D3 (1a) in spite of the absence of the conjugated triene structure typical of vitamin D compounds. The potency of these vitamin D endoperoxides (2 and 2'), especially those lacking the 1 alpha-hydroxyl group, in inducing differentiation of HL-60 cells was not correlated with their activity in binding to the cytosol receptor for 1 alpha, 25-dihydroxyvitamin D3 (1b). The binding efficiency to the receptor was relatively lower than the differentiating activity. To examine the action of vitamin D endoperoxides, carbon analogues of 25-(OH)D3 endoperoxides, two C-6 epimers of 25-hydroxy-6,19-dihydro-6,19-ethanovitamin D3 (6 and 6'), were synthesized. The carbon analogues (6 and 6') had no potential to induce differentiation of HL-60 cells. These results suggest that vitamin D endoperoxides (2 and 2') express their biological activity probably after being converted to some other compounds.     

Frequency of undetected CYP2D6 hybrid genes in clinical samples: impact on phenotype prediction

Cytochrome P450 2D6 (CYP2D6) is highly polymorphic. CYP2D6-2D7 hybrid genes can be present in samples containing CYP2D6*4 and CYP2D6*10 alleles. CYP2D7-2D6 hybrid genes can be present in samples with duplication signals and in samples with homozygous genotyping results. The frequency of hybrid genes in clinical samples is unknown. We evaluated 1390 samples for undetected hybrid genes by polymerase chain reaction (PCR) amplification, PCR fragment analysis, TaqMan copy number assays, DNA sequencing, and allele-specific primer extension assay. Of 508 CYP2D6*4-containing samples, 109 (21.5%) harbored CYP2D6*68 + *4-like, whereas 9 (1.8%) harbored CYP2D6*4N + *4-like. Of 209 CYP2D6*10-containing samples, 44 (21.1%) were found to have CYP2D6*36 + *10. Of 332 homozygous samples, 4 (1.2%) harbored a single CYP2D7-2D6 hybrid, and of 341 samples with duplication signals, 25 (7.3%) harbored an undetected CYP2D7-2D6 hybrid. Phenotype before and after accurate genotyping was predicted using a method in clinical use. The presence of hybrid genes had no effect on the phenotype prediction of CYP2D6*4- and CYP2D6*10-containing samples. Four of four (100%) homozygous samples containing a CYP2D7-2D6 gene had a change in predicted phenotype, and 23 of 25 (92%) samples with a duplication signal and a CYP2D7-2D6 gene had a change in predicted phenotype. Four novel genes were identified (CYP2D6*13A1 variants 1 and 2, CYP2D6*13G1, and CYP2D6*13G2), and two novel hybrid tandem structures consisting of CYP2D6*13B + *68×2 + *4-like and CYP2D6*13A1 variant 2 + *1×N were observed.