Effects of prepubertal zeranol exposure on estrogen target organs and N-methyl-N-nitrosourea-induced mammary tumorigenesis in female Sprague-Dawley rats

BACKGROUND: There are no previous reports of the effects of prepubertal exposure to zeranol, an estrogenic substance, on estrogen-responsive reproductive organs and mammary glands in rats, or its effects on N-methyl-N-nitrosourea (MNU)-induced mammary tumorigenesis in rats. MATERIALS AND METHODS: Prepubertal female Sprague-Dawley rats were treated daily with either 0, 0.1 or 10 mg/kg body weight of zeranol between 15 and 19 days of age. They were given 50 mg/kg body weight MNU at 28 days of age, and were monitored for occurrence of mammary tumors > or = 1 cm in diameter. Body weight gain, structures and functions of estrogen target tissues, and mammary carcinogenesis were compared between dosage groups. RESULTS: Zeranol did not affect body weight gain. At 28 days of age, zeranol-treated and -untreated rats showed similar development of reproductive organs and mammary glands. However, both low- and high-dose zeranol treatment caused significantly earlier vaginal opening, irregularity of estrous cycle (high frequency of prolonged estrous or prolonged diestrous) at 8 to 11 weeks of age, and anovulatory ovary (ovaries without newly formed corpora lutea). At 37 weeks of age, the high-dose zeranol-treated group exhibited increased relative uterine-ovarian weight, but mammary gland development was comparable to that of untreated rats. Mammary carcinogenesis was not affected by low- or high-dose zeranol treatment. CONCLUSION: Short-duration zeranol treatment in the prepubertal period severely damaged ovarian functions and structure, but mammary carcinogenesis was not affected. The present results suggest that ingestion of foods containing zeranol in the infantile period can cause dramatic endocrine disruption in later life.     

Effect of prenatal and prepubertal genistein exposure on N-methyl-N-nitrosourea-induced mammary tumorigenesis in female Sprague-Dawley rats

BACKGROUND: The effect of prenatal and prepubertal genistein exposure on the development of chemically-induced mammary carcinomas in rat was investigated. Materials and METHODS: Genistein was subcutaneously (s.c.) injected daily, from gestational days 15 to 19, into pregnant Sprague-Dawley rats at 0, 1.5 or 30 mg/kg/day. Female offspring of mothers not exposed to genistein during pregnancy received daily s.c. injection, from prepubertal days 15 to 19, at a dose of 1.5 or 30 mg/kg/day. At 28 days of age, 6 female offspring from each group were sacrificed to observe the influence of genistein and the remaining rats were injected intraperitoneally with 50 mg/kg N-methyl-N-nitrosourea (MNU). Rats injected with MNU were sacrificed at 26 weeks of age or when their largest mammary tumor was > or = 1 cm in size. RESULTS: At the time when MNU was administered, the different groups had comparable mammary gland development; genistein-treated and -untreated rats had similar numbers of terminal end buds (TEBs) at the periphery of the mammary glandular tree. However, estrogen receptor alpha (ER alpha)- and progesterone receptor (PgR)-positive cells, p63-positive cells and proliferating cell nuclear antigen (PCNA)-labeling index were lower in genistein-exposed TEBs. Although tumor multiplicity and latency were not significant, prenatal or prepubertal genistein exposure, at low or high dosage, tended to suppress the incidence of mammary carcinomas > or = 1 cm; suppression was significant in the prepubertal low-dose group. CONCLUSION: The majority of the mammary carcinomas in the present study were hormone-dependent. The present findings suggest that administration of genistein in the perinatal period has protective effects against MNU-induced mammary carcinoma in Sprague-Dawley rats, via reduction of levels of ER alpha- and/or PgR-positive cells (presumed progenitor cells of mammary carcinomas), p63-positive mammary progenitor/stem cells (involved in cell renewal) and PCNA-positive cells (necessary for cell proliferation).     

Effect of dietary lipid and dimethyl sulfoxide on lindane metabolism.

Previous investigations have suggested that there is a requirement of dietary polyunsaturated fatty acids for full expression of microsomal enzyme induction. The conclusions in these studies were primarily based on in vitro enzyme activity, sleeping time recovery, or hepatic cytochrome P-450 content, measured 24 hr after treatment with an inducing agent. This study set out to examine the influence of dietary lipids, containing different fatty acid compositions, on the storage and self-induction of lindane metabolism. The alteration in metabolism was followed on a daily basis throughout the treatment period. Twenty-four female weanling rats were fed fat-free diets either unsupplemented or supplemented with 7% hydrogenated coconut oil, 7% peanut oil, or 5% menhaden oil plus 2% linseed oil for 12 days prior to treatment with lindane. All rats then received a daily po dose of 2.5 mg of lindane in dimethyl sulfoxide (DMSO) for 7 days. On Day 8, all rats were treated with 2.5 mg of lindane (containing 1.93 μCi of [¹⁴C]lindane and they were sacrificed 24 hr later. Tissue samples were analyzed for radioactivity. Liver samples were assayed for microsomal phospholipid, protein, and cytochrome P-450 plus the enzymatic dehydrogenation of lindane. In addition, the fatty acid content of microsomal phosphatidylcholine (PC) and phosphatidylethanolamine (PE) was determined. Depressed food consumption and growth rate, an impaired metabolite excretion pattern, low specific microsomal phospholipid content, and a decreased microsomal $\text{PC}\text{PE}$ ratio containing a reduced proportion of polyunsaturated fatty acids suggested that a toxic lindane-DMSO-dietary lipid interaction had occurred.     

Effect of serum protein binding on sulfisoxazole distribution, metabolism, and excretion in rats.

This investigation determined the effect of serum protein binding on the kinetics of sulfisoxazole distribution, metabolism, and excretion. Adult rats, whose serum free fraction of sulfisoxazole (at a total concentration of 81 +/- 6 micrograms/ml) was 0.05-0.24, received a rapid intravenous injection of 20 mg/kg. Sulfisoxazole concentrations in plasma declined biexponentially with time. There were pronounced and reproducible interindividual differences in the total, metabolic, and renal sulfisoxazole clearances, each positively correlated with the serum free fraction of sulfisoxazole. The renal sulfisoxazole clearance had a component unaffected by serum protein binding. The apparent central compartment volume increased with an increasing serum free sulfisoxazole fraction, but the latter had not apparent effect on the first exponential term of the biexponential equation describing sulfisoxazole elimination kinetics in rats. Serum protein binding was a major determinant of intersubject differences in sulfisoxazole excretion and biotransformation kinetics.     

雌激素对老年雌性去势大鼠肝脏代谢能力及抗氧化功能的影响

目的:观察老年雌性去势大鼠补充乙烯雌酚后肝脏药物代谢酶活性及抗氧化功能的变化,并探讨更年期应用雌激素的生理学和药理学意义。方法:切除大鼠双侧卵巢造成雌激素锐减。术后d 3经口灌胃乙烯雌酚(10 0 μg·kg- 1,qd×4 0d) ,每天1次,连续4 0d。观察大鼠肝脏药物代谢酶活性和抗氧化指标的变化。结果:去势大鼠肝微粒体细胞色素P4 5 0及细胞色素b5含量显著降低,NADPH 细胞色素C还原酶、苄非他明N 脱甲基酶、氨基比林N 脱甲基酶活性也明显降低。肝微粒体及肝匀浆中谷胱甘肽S 转移酶活性显著降低,肝匀浆谷胱甘肽含量减少,脂质过氧化产物丙二醛增加。给予乙烯雌酚后,除对细胞色素b5无明显影响外,上述指标均可逆转。结论:老年雌性大鼠去势后肝脏代谢能力及抗氧化功能的降低与雌激素水平低下有关。乙烯雌酚能有效地改善上述变化,维持肝脏正常的代谢能力及抗氧化功能。     

Effect of ethanol/arrack on the lipid metabolism of mammary gland during pregnancy and lactation in rats

Female rats were exposed to arrack (12.0 ml/kg body weight/day) and ethanol (4.0 g/kg body weight/day) before conception and throughout gestation and lactation. On 19th day of gestation and 21st day of lactation there was increase in the cholesterol phospholipids, triglycerides and free fatty acids in the mammary gland of rats administered arrack/ethanol in comparison with the controls. The lipoprotein lipase activity showed significant increase in the treated groups, in which the activity decreased on 21st day in comparison with 19th day. The absolute and relative weight of mammary gland also showed a significant decrease in ethanol/arrack treated group. The biochemical alterations produced in the mammary gland by arrack and its equivalent alcohol were different showing that non-alcoholic portion of arrack interferes with the toxicity induced by alcohol. Arrack was found to be a potent hyperlipidemic agent than ethanol.     

Effect of propofol and ketamine on lipid metabolism and lipid peroxidation in rats

Ketamine (50 mg/kg, i.p.) increases the intensity of lipolysis in Wistar male rats, as manifested by increasing content of nonetherified fatty acids and cholesterol in the blood serum. This drug also enhances the lipid peroxidation (LPO) process, as manifested by the content of LPO products in the blood serum and in the liver and heart tissues. Propofol in the same dose also influences the lipid metabolism and LPO intensity, but to a lower extent.     

Distribution, metabolism and excretion of 14C-MT-141 in rats. II. Distribution and excretion after multiple intravenous administration in male rats and after single intravenous administration in female rats

The distribution and tissue accumulation of the radioactivity were studied in male rats after the multiple intravenous administration of 14C-MT-141. The distribution and the placental transfer were also studied using pregnant rats or lactating rats after the single intravenous administration of 14C-MT-141. The radioactive concentration in the fetus was low and the radioactivity was distributed almost uniformly through the fetus body. The peak time of the milk level was 2 hours after the administration and the radioactivity in milk decreased gradually thereafter. The milk levels decreased more slowly than the blood levels did. The blood level after the last dose administered daily for 7 days tended to decrease more slowly, when compared with the single administration. However the blood concentration at 48 hours after the last administration was less than 3 times as high as that after the single administration.     

琉璃苣油对脂质代谢和脂质过氧化的影响

在高脂饲料中加入６％的琉璃苣油饲喂Ｗｉｓｔａｒ♂大鼠３ｗｋ，其大鼠血清甘油三酯（ＴＧ）、总胆固醇（ＴＣ）、低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）、ＴＣ／ＨＤＬ－Ｃ、ＬＤＬ－Ｃ／ＨＤＬ－Ｃ增加值和高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）、高密度脂蛋白亚组分Ⅱ胆固醇（ＨＤＬ２－Ｃ）、ＨＤＬ２－Ｃ与高密度脂蛋白亚组分Ⅲ胆固醇ＨＤＬ３－Ｃ比值及卵磷脂胆固醇酰基转移酶（ＬＣＡＴ）活性的下降显著低于单纯食猪油的高脂对照组，琉璃苣油组大鼠血清ＬＤＬ－Ｃ水平低于月见草油组。高脂摄入所致大鼠肝脂质和肝过氧化脂质（ＬＰＯ）水平增高，谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活性下降，琉璃苣油致肝脂质过氧化作用低于月见草油。     

Modulation of N-nitrosomethylurea induced mammary tumorigenesis by dietary fat and voluntary exercise.

The effect of dietary fat and exercise on N-nitrosomethylurea [NMU:CAS:684-93-5]-induced mammary tumorigenesis in female F344 rats was investigated. Rats were fed the NIH-07 diet until NMU administration on day 50 of age, when they were transferred to four treatment groups. Three sedentary groups were fed either high-fat (20% wt/wt), medium fat (10%) or low fat (5%) diets (HF, MF, LF, respectively), and a fourth group was fed a HF diet but allowed free access to an activity wheel (HFEX). Tumor yields among the three sedentary groups were significantly greater in the HF and MF groups when compared to the LF group. Voluntary exercise reduced tumor yields and delayed time of tumor appearance in HFEX animals to levels similar to those found in LF sedentary animals. Animals with voluntary access to exercise wheels averaged between 1.03 and 2.85 miles/day, consumed more food (+ 18%) and exhibited greater weight gain (+ 13%) than their sedentary counterparts. No differences in weight gains were detected among the HF, MF, and LF groups, despite widely varying amounts of fat intake. Body composition studies indicated that body fat content was not influenced by the quantity of fat consumed in the diet, but was significantly reduced by voluntary exercise (-20%). Since exercise and fat intake have been associated with alterations in endocrine status, circulating bioactive and immunoactive prolactin were assessed at termination. No significant changes were found in either form of prolactin among the four experimental groups, casting doubt on mediation by this pituitary hormone.     

Effects of dietary Angelica keiskei on lipid metabolism in stroke-prone spontaneously hypertensive rats

1. The effect of dietary Angelica keiskei on lipid metabolism was examined in stroke-prone spontaneously hypertensive rats (SHRSP). 2. Six-week-old male SHRSP were fed diets containing 0.2% A. keiskei extract (ethyl acetate extract from the yellow liquid of stems) for 6 weeks with free access to the diet and water. 3. Elevation of systolic blood pressure tended to be suppressed on and after 2 weeks; however, this effect was not statistically significant. 4. Serum levels of cholesterol and phospholipid in SHRSP were significantly elevated after treatment with A. keiskei extract and this effect was accompanied by significant increases in serum apolipoprotein (Apo) A-I and ApoE concentrations. These changes in the serum were due to increases in high-density lipoprotein (HDL) containing ApoA-I and ApoE. 5. In the liver, significant decreases in relative weight and triglyceride content were observed in SHRSP after treatment with A. keiskei extract. An investigation of mRNA expression of enzymes involved in hepatic triglyceride metabolism indicated a decreased level of hepatic Acyl-coenzyme A synthetase mRNA expression. 6. In conclusion, dietary A. keiskei produces elevation of serum HDL levels and a reduction of liver triglyceride levels in SHRSP.     

Evaluation of the excretion, and metabolism of the cardiotonic agent bemoradan in male rats and female beagle dogs.

The excretion and metabolism of (+/-) [6-(3,4-dihydro-3-oxo-1,4[2H]-benzoxazine-yl)-2,3,4,5-tetrahydro-5-methylpyridazin-3-one] (bemoradan; RWJ-22867) have been investigated in male Long-Evans rats and female beagle dogs. Radiolabeled [14C] bemoradan was administered to rats as a singkle 1 mg/kg suspension dose while the dogs received 0.1 mg/kg suspension dose. Plasma (0-24 h; rat and dog), urine (0-72 h; rat and dog) and fecal (0-72 h; rat and dog) samples were collected and analyzed. The terminal half-life of the total radioactivity for rats from plasma was estimate to be 4.3 +/- 0.1 h while for dogs it was 7.5 +/- 1.3 h. Recoveries of total radioactivity in urine and feces for rats were 49.1 +/- 2.4% and 51.1 +/- 4.9% of th dose, respectively. Recoveries of total radioactivity in urine and feces for dogs were 56.2 +/- 12.0% and 42.7 V 9.9% of the dose, respectively. Bemoradan and a total of nine metabolites were isolated and tentatively identified in rat and dog plasma, urine, and fecal extracts. Unchanged bemoradan accounted for approimately < 2% of the dose in rat urine and 20% in rat feces. Unchanged bemoradan accounted for approximately 5% of the dose in urine and 16% in feces in dog. Six proposed pathways were used to describe the metabolites found in rats and dogs: pyridazinyl oxidations, methyl hydroxylation, hydration, N-oxidation, dehydration and phase II conjugations.     

Effect of short- vs. long-term estrogen on reinstatement of cocaine-seeking behavior in female rats

Estrogen effects on cocaine-induced reinstatement of lever responding were examined in sham-operated, vehicle-treated (SH+VEH), ovariectomized (OVX+VEH), and OVX female Wistar rats with estrogen replacement (OVX+EB). The effect of long- (64+/-1.56 days) and short-term (9 days) EB treatment on reinstatement of cocaine-seeking behavior was compared in Experiment 1 and 2, respectively, in order to compare the effect of EB when it was present during the development vs. expression of reinstatement of cocaine-seeking behavior. Rats were trained to self-administer 0.4 mg/kg/inf cocaine. After the acquisition criteria were met, rats continued to respond for cocaine for 2 h/day for a 14-day maintenance period. Cocaine was then replaced with saline and the 21-day extinction period commenced. Subsequently, rats were tested for reinstatement of lever responding on the previously drug-paired lever after alternating daily injections of saline or cocaine. In both experiments, there were no differences between groups in self-administration behavior during training, maintenance, or extinction. In Experiment 1, SH+VEH and chronically treated OVX+EB rats had greater cocaine-induced reinstatement than OVX+VEH rats. In Experiment 2, short-term treated OVX+EB rats also showed enhanced cocaine-induced reinstatement compared to OVX+VEH rats. The results indicate that EB-mediated enhancement of cocaine-induced reinstatement is dependent on EB presence during the expression of reinstatement but not during the formation of stimulus-reward associations during the development of cocaine-reinforced behavior.     

Bioavailability and mammary excretion of bisphenol a in Sprague-Dawley rats.

This study reports the absolute oral bioavailability and mammary excretion of bisphenol A in rats. The oral bioavailability was determined after administration of relatively low iv (0.1 mg/kg) and oral (10 mg/kg) doses of bisphenol A to rats. After iv injection, serum levels of bisphenol A declined biexponentially, with the mean initial distribution and terminal elimination half-lives being 6.1 +/- 1.3 min and 52.5 +/- 2.4 min, respectively. The systemic clearance (Cls) and the steady-state volume of distribution (Vss) averaged 107.9 +/- 28.7 m/min/kg and 5.6 +/- 2.4 L/kg, respectively. Upon oral administration, the maximum serum concentration (Cmax) and the time to reach the maximum concentration (Tmax) were 14.7 +/- 10.9 ng/ml and 0.2 +/- 0.2 h, respectively. The apparent terminal elimination half-life of bisphenol A (21.3 +/- 7.4 h) after oral administration was significantly longer than that after iv injection, indicating the flip-flop of the absorption and elimination rates. The absolute oral bioavailability of bisphenol A was low (5.3 +/- 2.1%). To determine the extent of mammary excretion, bisphenol A was given by simultaneous iv bolus injection plus infusion to steady state at low, medium, and high doses. The steady-state serum levels of bisphenol A were linearly increased with higher dosing rates. The systemic clearance (mean range, 119.2-154.1 ml/min/kg) remained unaltered over the dosing rate studied. The levels of bisphenol A in milk exceeded those in serum, with the steady-state milk to serum concentration ratio being 2.4-2.7.     

Distribution, excretion, and metabolism of nitro-p-phenylenediamine in rats

The distribution, excretion, and metabolism of nitro-p-phenylenediamine, a constituent of hair dye, was studied after administration of [14C]nitro-p-phenylene-diamine (2.6 mg/30 microCi/kg) to male rats. After intraperitoneal administration, 37.4% of the radioactivity administered was excreted in the urine and 54.3% in the feces within 24 h. After intravenous administration, 42.2% of the radioactivity was excreted in the bile within 24 h. The highest concentration of radioactivity in tissues was found at 1 h, except in the small and large intestines, followed by a rapid decrease in concentration. Only small amounts of radioactivity were found in the tissues 48 h after administration. Some of the radioactive materials in the urine were separated by thin-layer chromatography and identified as N1,N4-diacetyl-2-amino-p-phenylenediamine, N4-acetyl-2-nitro-p-phenylenediamine, and unchanged nitro-p-phenylenediamine.     

灵仙新苷对高脂血症大鼠早期动脉粥样硬化的干预作用

目的:研究灵仙新苷(clematichinenoside AR)调节血脂及抗动脉粥样硬化的作用。方法:采用高脂饲料喂饲和腹腔注射维生素D3结合腹腔注射LPS建立大鼠动脉粥样硬化模型,造模成功后灌胃给予高、中、低剂量的AR(32,16,8 mg.kg-1.d-1),8周后测定大鼠血清胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白-胆固醇(HDL-C)、低密度脂蛋白-胆固醇(LDL-C)、肿瘤坏死因子(TNF-α)、一氧化氮(NO)及诱导型一氧化氮合酶(iNOS);取其胸主动脉进行油红O染色,观察大鼠胸主动脉内膜脂质沉积情况;取肝脏进行常规HE染色,观察肝脏病变。结果:AR高、中剂量组能显著降低高血脂症大鼠血清TC,TG,LDL-C,TNF-α,NO水平和iNOS活力,升高HDL-C水平,差异具有统计学意义(P<0.05)。同时,AR能减少主动脉内皮脂质沉积,改善肝脏的脂肪变性和炎症细胞浸润。结论:AR具有调节血脂,减轻动脉粥样硬化发生和发展的作用,该作用与其调节NO及其合酶的形成和表达相关。     

Effect of KRN4884 on lipid metabolism in hyperlipidemic rats

• 1.1. KRN4884 is a novel pyridinecarboxamidine type potassium channel opener.
• 2.2. To determine whether KRN4884 affects lipid metabolism, we investigated its effects on serum lipid levels by using two types of hyperlipidemic rats: genetically hyperlipidemic obese Zucker rats and diet-induced hyperlipidemic rats fed a high fat diet. KRN4884 dose dependently decreased systolic blood pressure in Zucker rats.
• 3.3. Oral administration of KRN4884 (1–10 mg/(kg day) for 14 days dose dependently reduced serum triglyceride levels in Zucker rats. The reductions in serum triglyceride were associated with reductions in triglyceride in chylomicron and very low density lipoprotein.
• 4.4. KRN4884 produced no change in serum insulin and glucose levels in Zucker rats.
• 5.5. KRN4884 exhibited a similar triglyceride lowering effect in diet-induced hyperlipidemic rats.
• 6.6. These results suggest that KRN4884 has a beneficial effect on serum triglyceride levels as well as a hypotensive effect.

     

Pharmacokinetics, tissue distribution, metabolism, and excretion of celecoxib in rats.

The pharmacokinetics, tissue distribution, metabolism, and excretion of celecoxib, 4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl] benzenesulfonamide, a cyclooxygenase-2 inhibitor, were investigated in rats. Celecoxib was metabolized extensively after i.v. administration of [(14)C]celecoxib, and elimination of unchanged compound was minor (less than 2%) in male and female rats. The only metabolism of celecoxib observed in rats was via a single oxidative pathway. The methyl group of celecoxib is first oxidized to a hydroxymethyl metabolite, followed by additional oxidation of the hydroxymethyl group to a carboxylic acid metabolite. Glucuronide conjugates of both the hydroxymethyl and carboxylic acid metabolites are formed. Total mean percent recovery of the radioactive dose was about 100% for both the male rat (9.6% in urine; 91.7% in feces) and the female rat (10.6% in urine; 91.3% in feces). After oral administration of [(14)C]celecoxib at doses of 20, 80, and 400 mg/kg, the majority of the radioactivity was excreted in the feces (88-94%) with the remainder of the dose excreted in the urine (7-10%). Both unchanged drug and the carboxylic acid metabolite of celecoxib were the major radioactive components excreted with the amount of celecoxib excreted in the feces increasing with dose. When administered orally, celecoxib was well distributed to the tissues examined with the highest concentrations of radioactivity found in the gastrointestinal tract. Maximal concentration of radioactivity was reached in most all tissues between 1 and 3 h postdose with the half-life paralleling that of plasma, with the exception of the gastrointestinal tract tissues.     

The metabolism and excretion of galantamine in rats, dogs, and humans.

Galantamine is a competitive acetylcholine esterase inhibitor with a beneficial therapeutic effect in patients with Alzheimer's disease. The metabolism and excretion of orally administered (3)H-labeled galantamine was investigated in rats and dogs at a dose of 2.5 mg base-Eq/kg body weight and in humans at a dose of 4 mg base-Eq. Both poor and extensive metabolizers of CYP2D6 were included in the human study. Urine, feces, and plasma samples were collected for up to 96 h (rats) or 168 h (dogs and humans) after dosing. The radioactivity of the samples and the concentrations of galantamine and its major metabolites were analyzed. In all species, galantamine and its metabolites were predominantly excreted in the urine (from 60% in male rats to 93% in humans). Excretion of radioactivity was rapid and nearly complete at 96 h after dosing in all species. Major metabolic pathways were glucuronidation, O-demethylation, N-demethylation, N-oxidation, and epimerization. All metabolic pathways observed in humans occurred in at least one animal species. In extensive metabolizers for CYP2D6, urinary metabolites resulting from O-demethylation represented 33.2% of the dose compared with 5.2% in poor metabolizers, which showed correspondingly higher urinary excretion of unchanged galantamine and its N-oxide. The glucuronide of O-desmethyl-galantamine represented up to 19% of the plasma radioactivity in extensive metabolizers but could not be detected in poor metabolizers. Nonvolatile radioactivity and unchanged galantamine plasma kinetics were similar for poor and extensive metabolizers. Genetic polymorphism in the expression of CYP2D6 is not expected to affect the pharmacodynamics of galantamine.