根田鼠气味识别的性二型

以新鲜尿和粪作气味源,在行为选择箱中观察根田鼠的行为识别模式,结果表明：雌鼠对陌生同性尿、粪气味源行为识别的差异不显,雄鼠对陌生同性尿、粪气味源的行为识别在多个指标上存在显差异;根田鼠对陌生异性尿、粪的行为响应模式无明显差异;除嗅舔时间外,雌、雄鼠对粪气味的行为识别在其他指标上不存在明显差异;比较雌、雄鼠对尿刺激的行为识别发现,雄鼠对尿刺激的访问频次和反标记显大于雌鼠,雌性嗅舔时间显大于雄性,其他方面二之间并无显差异。因此,雌、雄性根田鼠对粪气味的行为识别模式不存在性别差异;对尿气味的行为识别模式存在性别差异。     

High-performance liquid chromatographic assays for a second-generation novel oral iron chelator (APCP363) and their application to pharmacokinetic studies in rats

Sensitive and specific HPLC assays for APCP363 in biological matrices (rat plasma, urine and feces) were developed. The recovery of APCP363 ranged from 81.2 to 99.9% in plasma, from 82.1 to 92.8% in urine, and from 65 to 68% in feces. Standard deviations were below 10% for all analyses. The limits of quantitation were 0.1, 10 and 30 μg/ml in plasma, urine and feces, respectively. The HPLC assays, which are the first reports for APCP363 analysis in biological matrices, have been successfully applied to preliminary pharmacokinetic studies in rats. The stool assay is the first non-radiolabeled method for hydroxypyridinones in feces.     

Metabolism and Calcium Antagonism of Sodium Alginate Oligosaccharides

Sodium alginate oligosaccharides (NaAOs) consisting of a mixture of eight oligosaccharides have previously been reported to lower blood pressure. We investigated in this study the excretion of NaAOs into the urine or feces, and attempted to elucidate the mechanism for lowering blood pressure by using isolated mesenteric arteries from the rabbit. The recovery rate of P8, which is the main component of NaAOs, was 5.2% and 58.9% over 48 hours in the urine and feces, respectively. The mechanism for lowering blood pressure appeared to be NaAOs having calcium antagonist activity, especially voltage-operated calcium channels. Our results suggest that NaAOs are substantially excreted into the feces, although some of them may be absorbed internally, exerting antagonist activity towards the calcium channels, especially voltage-operated calcium channels.     

Metabolism and calcium antagonism of sodium alginate oligosaccharides

Sodium alginate oligosaccharides (NaAOs) consisting of a mixture of eight oligosaccharides have previously been reported to lower blood pressure. We investigated in this study the excretion of NaAOs into the urine or feces, and attempted to elucidate the mechanism for lowering blood pressure by using isolated mesenteric arteries from the rabbit. The recovery rate of P8, which is the main component of NaAOs, was 5.2% and 58.9% over 48 hours in the urine and feces, respectively. The mechanism for lowering blood pressure appeared to be NaAOs having calcium antagonist activity, especially voltage-operated calcium channels. Our results suggest that NaAOs are substantially excreted into the feces, although some of them may be absorbed internally, exerting antagonist activity towards the calcium channels, especially voltage-operated calcium channels.     

Metabolic products of arachidonic acid in rats

The pattern of eicosanoid metabolites appearing in urine and feces following oral administration of radioactive arachidonic acid was investigated using rats deficient in essential fatty acids. About 70-80% of the radioactivity in the urine during the first day after feeding was adsorbed to XAD-2 resin and represented eicosanoid metabolites, whereas the rest of the radioactivity was mainly 3H2O. The eicosanoid metabolites were fractionated into different polarity classes using reverse phase Sep-Pak C18 cartridges. Gas chromatographic analysis of the urinary metabolites following their derivatization into methyl ester-methoxime-tert-butyl-dimethylsilyl ethers revealed that nearly one-half of the metabolites had ECL values less than 22 and represented metabolites more oxidized than commonly described. Only 30% of the metabolites had ECL values between 26 to 32, corresponding to the values for the metabolites that originate from exogenously infused prostaglandins. A large portion of the eicosanoid metabolites was also excreted with the feces. The isotopic patterns from the reverse phase chromatography indicated that many of the fecal metabolites may be similar to those in urine although some metabolites in feces were not present in urine. Based on the specific radioactivity of the administered arachidonic acid, it appeared that at least 6 to 8 mg of eicosanoid metabolites were excreted through urine and feces within 24 hrs following an oral bolus of 60 mg arachidonic acid. The rapid increase and subsequent decrease in eicosanoid metabolite excretion after oral administration of arachidonate indicates that the dietary intake of polyunsaturated fatty acids may have a more rapid effect upon the endogenous production of eicosanoids than is generally recognized.     

The effect of a synthetic steroid (trienbolone) on the rate of release and excretion of subcutaneously administered estradiol in calves (18).

With the objective of obtaining values for the rate of release and excretion of subcutaneously implanted estradiol and to relate them to the metabolic effect of the hormone, a study was carried out with young Jersey bull calves. After subcutaneous administration of lactose tablets (implants) containing tritiated estradiol (4 mCi in 20 mg estradiol) the activity was followed in plasma, urine and feces for 107 days. Three calves received implants containing 140 mg trienbolone in addition to the 20 mg estradiol. In the first group maximum plasma concentration of estradiol-17 beta was 3 nmol/1. In the other group it was only 0.33 nmol/1. In calves receiving estradiol as the only steroid, 95% of the activity was excreted within 20 days after implantation. In the other group collection of urine and feces had to be carried out for 107 days in order to account for all the implanted activity. No 3H could be detected in urine and feces samples collected from the estradiol group more than 31 days ater implantation. The feces and urine samples collected from calves in the estradiol-trienbolone group 107 days after implantation contained from 1.4 - 3 nCi per gram. The remarkably decreasing effect of trienbolone on the release of estradiol and its possible importance for the effect of subcutaneously administered estradiol are discussed.     

A Simple, Inexpensive Metabolism Cage for Small Mammals

By utilizing ordinary laboratory equipment and a spherical feces-urine separator, a simple, inexpensive metabolism cage for small mammals can be constructed. A hardware cloth animal cage over a cylindrical battery jar containing a spherical feces-urine separator affords the following advantages not commonly found in commercial metabolism cages: 1) complete separation of feces and urine through minimal contact, 2) minimal evaporation of urine due to proximity of storage vessel and lack of exogenous air currents, and 3) extremely low cost of less than five dollars. The metabolism cage is designed to allow measurement of fluid intake, and to separate and collect feces and urine for numerous qualitative and quantitative determinations. In addition, the metabolism cage permits observation of the animal, feces, and urine at all times, is readily cleaned or sterilized, and is easily fashioned from common laboratory equipment.     

Metabolic products of arachidonic acid in rats

The pattern of eicosanoid metabolites appearing in urine and feces following oral administration of radioactive arachidonic acid was investigated using rats deficient in essential fatty acids. About 70–80% of the radioactivity in the urine during the first day after feeding was adsorbed to XAD-2 resin and he represented eicosanoid metabolites, whereas the rest of the radioactivity was mainly ³H₂O. The eicosanoid metabolites were fractioned into different polarity classes using reverse phase Sep-Pak C₁₈ cartridges. Gas chromatographic analysis of the urinary metabolites following their derivatization into methyl ester-methoxime- -butyl-dimethylsilyl ethers revealed that nearly one-half of the metabolites had ECL values less than 22 and represented metabolites more oxidized than commonly described. Only 30% of the metabolites had ECL values between 26 to 32, corresponding to the values for the metabolites that originate from exogenously infused prostaglandins. A large portion of the eicosanoid metabolites was also excreted with the feces. The isotropic patterns from the reverse phase chromatography indicated that many of the fecal metabolites may be similar to those in urine although some metabolites in feces were not present in urine. Based on the specific radioactivity of the administered arachidonic acid, it appeared that at least 6 to 8 mg of eicosanoid metabolites were excreted through urine and feces within 24 hrs following an oral bolus of 60 mg arachidonic acid. The rapid increase and subsequent decrease in eicosanoid metabolite excretion after oral administration of arachidonate indicates that the dietary intake of polyunsaturated fatty acids may have a more rapid effect upon the endogenous production of eicosanoids than is generally recognized.     

布氏田鼠在不同光周期下对陌生个体尿液和粪便的气味辨别

研究了成年布氏田鼠在10min内,对不同光照周期下（长光照：LD;短光照：SD）陌生雌／雄个体尿液和粪便两种单一个体气味源的气味行为反应,实验发现：所有雌雄被试鼠对LD气味源比SD气味源表现出更多的嗅闻行为。LD和SD被试鼠对同性／异性尿液气味的嗅闻行为没有表现出明显的差别,但LD被试雄鼠对陌生雌鼠粪便的嗅闻频次显多于SD被试雄鼠,从嗅闻行为特征量（嗅闻行为占所有行为的百分比）来看,所有LD和SD被试雌,雄鼠对尿液的嗅 明显多于粪便,除SD粪便气味外,被试鼠对异性气味源的嗅闻明显多于同性,实验结果表明：作为两种个体气味源,尿液和粪便都带有季节性信息,而且是具有性别特性的。异性的个体气味源比同性的个体气味源更具吸引力;长光照动物的个体气味比短光照动物的气味更具吸引力。     

Human urine and chicken feces as fruit fly (Diptera: Tephritidae) attractants for resource-poor fruit growers

We evaluated human urine and chicken feces, two naturally occurring, inexpensive, and readily available substances, as baits for the capture of Anostrepha spp. (Diptera: Tephritidae) by using glass McPhail traps. Two studies were performed simultaneously in a commercial mango orchard in Veracruz, México. In the first study, we compared a 50% water dilution of human urine against hydrolyzed protein, both compounds at the fresh and 5-d-old stages, and water alone (control treatment). In the second study, we tested fresh chicken feces mixed with water, a torula yeast/borax solution at three different ages (1-4, 5-9, and 10-15 d), and water (control treatment). Both human urine and chicken feces were attractive to Anastrepha adults compared with water alone, but attracted two and three times fewer adults than hydrolyzed protein and torula yeast/borax, respectively. However, unlike torula yeast/borax, aging of human urine did not decrease its attractiveness. Five-day old human urine attracted numerically more A. serpentina females than males, similar numbers of A. obliqua males and females, and significantly more sexually immature A. obliqua females than mature ones. Chicken feces proved to be as attractive as the aged torula yeast/borax treatments for A. obliqua and A. serpentina. We argue that because both human urine and chicken feces are cost-free and can be easily obtained, they are viable, low-technology alternatives to costly commercial attractants, particularly for low-income growers or backyard farmers in Mexico and other Latin American countries.     

The analysis of arildone in plasma,urine and feces by gas—liquid chromatography with electron-capture detection

The analysis of arildone in plasma, urine and feces by gas—liquid chromatography with electron-capture detection is described. O-(2,3,4,5,6-Pentafluorohenzyl)hydroxylamine is the derivatizing agent for the plasma and urine analysis; 3-nitrophenylhydrazine is utilized for fecal analysis. The mean (± S.E.) minimum quantifiable level of arildone was 1.4 (± 0.2) ng/ml in urine, 6.4 (± 0.1) ng/ml in plasma, and 12.6 (± 1.0) ng/g in feces. The chromatographic response was linear in the range of 0 and 10–120 ng/ml for plasma, 0 and 2.5–20 ng/ml for urine and 0 and 25–250 ng/g for feces. The estimated overall precision of the assay was 5.5%, 6.4% and 8.9% in urine, plasma and feces, respectively.     

A note on the structure of tail hairs from a pygmy hippopotamus (Choeropsis liberiensis)

The pygmy hippopotamus (Choeropsis liberiensis), like the Nile hippopotamus (Hippopotamus amphibius), defecates by backing into vertical objects while making a series of rapid, propellerlike tail movements that spread a mixture of urine and feces in a wide swath. Split hairs from the distal ventral surface of the pygmy hippopotamus tail were studied with the scanning electron microscope to determine whether the splitting was a normal character of the hair or was due to damage. The results suggest that splitting is a normal feature of the hair that may facilitate the dispersal of urine and feces.     

Role of biocomponents of the bile and excreta in the elimination of plutonium and americium from the body

A study was made of the role of biocomponents of bile, urine and feces in the elimination of plutonium and americium from the organism. Plutonium 239 and americium 241 were separated in bile due to higher tropism of plutonium to low molecular weight ligands, and of americium, to a protein-containing fraction. The status of plutonium excreted in feces was the same as the physicochemical status of americium. Plutonium 239 and americium 241 eliminated in urine were in a completely ultrafiltered state.     

Fecal cup for collection of feces in male rats

A cup was designed which fits around the tail of male rats. The cup was used to collect feces and made it possible to separate urine and feces completely from each other. The cup was easy to apply, remove, empty and replace, and its use did not cause noticeable stress to the animal.     

Bacterially synthesized folate and supplemental folic acid are absorbed across the large intestine of piglets

A large pool of folate exists in the large intestine of humans. Preliminary evidence, primarily in vitro, suggests that this folate may be bioavailable. The purpose of this study was to test the hypothesis that supplemental folic acid and bacterially synthesized folate are absorbed across the large intestine of piglets. The pig was used as an animal model because it resembles the human in terms of folate absorption, at least in the small intestine. A tracer of [3H]-folic acid or [3H]-para-aminobenzoic acid ([3H]-PABA), a precursor of bacterially synthesized folate, was injected into the cecum of 11-day-old piglets. Feces and urine were collected for 3 days. Thereafter, piglets were killed, and livers and kidneys harvested. [3H]-Folate was isolated from biological samples by affinity chromatography using immobilized milk folate binding proteins and counted using a scintillation counter. In piglets injected with [3H]-folic acid, the feces, liver, urine and kidneys accounted for 82.1%, 12.3%, 3.9% and 1.7% of recovered [3H]-folate, respectively. In piglets injected with [3H]-PABA, the amount of recovered bacterially synthesized folate in the feces, liver and urine was 85.1%, 0.4% and 14.6%, respectively. Twenty-three percent and 13% of tritium were recovered in samples examined (liver, kidney, fecal and urine) from piglets injected with [3H]-folic acid and [3H]-PABA, respectively. Using our estimates of [3H]-folic acid absorption and the total and percent monoglutamyl folate content of piglet feces, we predict that at least 18% of the dietary folate requirement for the piglet could be met by folate absorption across the large intestine.     

Correlations of Trace Element Levels in the Diet,Blood, Urine,and Feces in the Chinese Male

In order to explore the associations between trace elements in dietary intake and the other three biological media (blood, urine, or feces) and inter-element interactions among the latter, we simultaneously collected 72-h diet duplicates, whole blood, and 72-h urine and feces from 120 free-living healthy males in China. Correlations among the toxic (cadmium [Cd], lead [Pb]), and nutritionally essential (zinc [Zn], copper [Cu], iron [Fe], manganese [Mn], selenium [Se], iodine [I]) elements were evaluated using Spearman rank correlation analysis based on analytical data determined by inductively coupled plasma-mass spectrometry. Dietary Cd intakes were highly correlated with the fecal Cd and blood Cd levels. Inverse correlations were found for Fe–Cd and Fe–Pb in both diet versus blood and diet versus feces. Cd–Zn and Cd–Se were significantly directly correlated in the urine and feces. Cd–Se and Pb–Se were negatively correlated in blood. In addition, there existed an extremely significant association between urinary Se and urinary I. Moreover, the other two highly direct correlations were found for Se–Fe and for I–Fe in urine. Improved knowledge regarding their mutual associations is considered to be of fundamental importance to understand more the complex interrelationships in trace element metabolism.     

烧伤大鼠常规营养物质代谢的变化

选取体重为200g左右的健康雄性普通级Wistar大鼠20只,随机分为烧伤组和对照组,分别单饲于大鼠代谢笼中,研究烧伤大鼠常规营养物质代谢的变化情况。实验结果表明烧伤不同程度地降低(P＜0.01或0.05)大鼠的采食量、排粪量、排尿量以及粪中蛋白质、粗脂肪和钙、磷的含量,而提高(P＜0.01或0.05)饲料中蛋白质、粗脂肪和钙、磷的消化率以及尿中氮的含量,烧伤后最初3天这种变化更为明显,体现了大鼠在烧伤应激状态下的代谢补偿作用和烧伤后的高分解代谢反应。     

Improved high-performance liquid chromatographic method for the pharmacokinetic studies of a novel iron chelator, CP502, in rats

An improved reverse-phase high-performance liquid chromatographic method (RP-HPLC) for the determination of a novel iron chelator CP502 (1,6-dimethyl-3-hydroxy-4-(1H)-pyridinone-2-carboxy-(N-methyl)-amide hydrochloride) in rat plasma, urine and feces was developed and validated. The separation was performed on a polymeric column using a mobile phase composed of 1mM ethylenediaminetetra-acetic acid disodium salt (EDTA), acetonitrile, methanol and methylene chloride. Separation of CP502 from plasma, urine or feces endogenous compounds was achieved by gradient elution. Retention times of CP502 and its major metabolite (glucuronide) were about 13 and 4 min, respectively. The method was validated in terms of limit of detection (LOD), limit of quantification (LOQ), selectivity (endogenous from plasma, urine or feces), linearity, extraction recovery, robustness (column selection, mobile phase composition, detection mode, internal standard (IS) selection, analyte stability), day-to-day reproducibility and system suitability (repeatability, peak symmetry and resolution). The method is applicable to bioavailability and pharmacokinetic studies of CP502 in rats.     

Excretion of radiolabeled estradiol in the cat (Felis catus,L): A preliminary report

The time course and end products of estradiol metabolism were studied in the domestic cat, which has been chosen as a model for steroid metabolism studies in nondomestic felidae. Radiolabeled estradiol was injected intravenously into three adult female cats; one had a spontaneous estrus, one was induced with follicle-stimulating hormone, and one had been ovariohysterectomized; feces, urine, and blood were collected daily, and the radioactivity content was determined. Feces and urine contained 47 and 1% of the injected dose (0.33 μCi), respectively. Metabolites appeared earlier in the urine than in feces (d 1 vs d 2 postinjection), and excretion was completed on d 5; no radioactivity was detected in plasma 24 h postinjection. Estradiol metabolites were excreted as unconjugated estrogens (22%) and as conjugates hydrolyzable with β-glucuronidase and acid solvolysis (7 and 50%, respectively); the remaining 14% were not recoverable with any of the above methods. The major portion of the conjugates was estradiol-17β (64–80%) while 11–16% appeared as estrone. Endogenous cycles related to the spontaneous and induced ovarian activity were monitored by observation of estrous behavior, vaginal epithelium cornification, and plasma estradiol determination. The reproductive state of each animal had no effect on the time course or type of metabolite excreted. We found low proportions of injected radioactivity excreted in the urine and high residual levels remaining after hydrolysis and extraction in the feces. These findings suggest that although feces are an abundant source of estradiol metabolite in the cat, and probably in the exotic felidae, development of noninvasive methods for monitoring ovarian cycles in these species will depend on more efficient methods for urine hydrolysis, on the resolution of problems encountered in fecal steroid analysis, or on the identification of metabolites which may be measured directly in the urine without hydrolysis or extraction.     

Dopamine β-hydroxylase: Determination of half-life and appearance in lymph fluid after IV injection of 125I-DBH into rats

A 4 day half-life of dopamine beta-hydroxylase (DBH) was determined for rats injected IV with ¹²⁵I-rat DBH from the slow exponential component of radioactivity appearing in plasma, urine, feces and combined urine and feces. Half-life estimates for ¹²⁵I-rat DBH injected IV into WKY and SHR animals did not differ from Sprague Dawley (Zivic Miller) rats. Radioactivity declined in parallel in plasma, urine and feces following IV ¹²⁵I-rat DBH administration and each radioactivity falloff curve could be resolved into two components. The slow phase of the decline of radioactivity excreted into urine and feces from which DBH half-life was calculated occurred between 5 and 25 days after ¹²⁵I-rat DBH injection. The early fast phase which is associated with distribution of the exogenous protein in body fluids and tissues continued for approximately the first 140 hr after DBH injection. The distribution characteristics of IV administered active bovine DBH and ¹²⁵I-rat DBH into the lymphatic system were examined. After active bovine DBH or ¹²⁵I-rat DBH was injected IV into rats, active DBH or radioactivity, respectively, appeared in lymph fluid (thoracic duct) within 20 min; reached peak concentrations within 90 min, and thereafter, declined in parallel with the plasma concentration. The concentration of radioactivity in plasma and lymph fluid were found to be unequal at 9 hr but were equivalent 68–75 hrs after IV injection of ¹²⁵I-rat DBH. Based on the amount of active DBH or radioactivity which accumulates in lymph fluid it is clear that'a substantial amount (> 50%) of the DBH in blood circulates through the lymphatic channels. Analysis of parallel experiments with labelled serum albumin indicate that use of these methods to study plasma proteins do provide sensitive measures of biological half-life and lymphatic distribution characteristics. Specifically for DBH, the results of our study suggest that DBH normally circulates in plasma and lymph fluid with a biological half-life of 4 days.