17α-甲基睾丸素及其某些衍生物对去势大鼠和小鼠同化作用的观察

本文用去势大鼠和小鼠研究17α-甲基睾丸素(Ⅰ)及一些衍生物的同化和雄性素样作用。同化作用指标是观察大、小鼠提肛肌和小鼠腎脏重量的增加,雄性素样作用是以精囊重量的增加来表示。結果指出,I的双氫衍生物——17α-甲基-(5α-雄甾烷-17β-羥-3-酮(Ⅱ)和17α-甲基-(5α)-雄甾烷-3β,17β-二羥(Ⅲ)的口服剂量为30毫克/公斤时,在去势大鼠的同化和雄性素样作用与I无显著不同。剂量12.5毫克/公斤肌肉注射时,則Ⅱ对去势小鼠的同化作用比I显著增强,雄性素样作用与I无显著不同;而Ⅲ的同化作用和雄性素样作用均有减弱。17α-甲基-(5α)-雄甾烷-17β-羥(Ⅳ)系I的3位脫氧衍生物,当給去势大鼠口服30毫克/公斤时,其同化作用比I显著增强;給去势小鼠肌肉注射12.5毫克/公斤时,其同化作用与I大致相同,但雄性素样作用只有I的1/3,因之,同化与雄性素样作用比值高至3.63—4.50。睾丸素17位脫氧衍生物——5α-雄甾烷-3-羥(Ⅴ)和5α-雄甾烷-3-酮(Ⅵ)的剂量为30—40毫克/公斤时,无論口服或注射,在去势大鼠和小鼠均不出現同化和雄性素样作用。以上結果表明,将化合物I 4,5位氫化和3位脫氧,可使同化作用:雄性素样作用比值明显提高,17位脫氧則失去同化和雄性素样作用。     

Oral administration of beta-cryptoxanthin induces anabolic effects on bone components in the femoral tissues of rats in vivo

The effect of beta-cryptoxanthin on bone components in the femoral tissues of rats was investigated. Beta-cryptoxanthin was isolated from Satsuma mandarin (Citrus unshiu MARC.). Bone tissues were cultured for 48 h in serum-free Dulbecco's modified Eagle's medium containing either vehicle or beta-cryptoxanthin (10(-7) or 10(-6) M). The presence of beta-cryptoxanthin (10(-7) or 10(-6) M) caused a significant increase in calcium content and alkaline phosphatase activity in the femoral-diaphyseal and femoral-metaphyseal tissues. These increases were completely abolished in the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis. Thus beta-cryptoxanthin had an anabolic effect on bone calcification in vitro. Moreover, beta-cryptoxanthin (10, 25, or 50 microg/100 g body weight) was orally administered once daily for 7 d to young male rats. The administration of beta-cryptoxanthin (10, 25, or 50 microg/100 g body weight) caused a significant increase in calcium content and alkaline phosphatase activity in the femoral-diaphyseal and femoral-metaphyseal tissues. Femoral-diaphyseal and femoral-metaphyseal DNA contents were significantly increased by the dose of 25 or 50 microg/100 g body weight. A significant increase in metaphyseal DNA content was also seen with the dose of 10 microg/100 g body weight of beta-cryptoxanthin. This study demonstrates that beta-cryptoxanthin has an anabolic effect on bone components in rats in vitro and in vivo.     

Comparative study of anabolizing activity of apilac and methandrostenolone on a model of isolated overload of the rat skeletal muscle

The anabolic activity of apilac was studied in rats in comparison to methanrdostenolone A 10-day administration of apilac (200 mg/kg) produced a pronounced anabolic effect manifested by a hypertrophy of m. soleus. Methanrdostenolone (10 mg/kg) also favored a gain in the muscle weight. The anabolic action of apilac was comparable to that of methanrdostenolone.     

Persistence of drug experience in rats formerly dependent on phenobarbital or meprobamate

The rats of groups I, II, III and IV were treated orally with phenobarbital, meprobamate, codeine and vehicle, respectively, for total 21 days, and then drugs were withdrawn. All these rats were given again orally phenobarbital for 5 days starting from 70 days after the withdrawal. In comparison with groups III and IV, groups I and II showed larger weight gain during phenobarbital re-administration and longer-lasting weight loss and an larger increase in body temperature after the termination. These results suggested that the drug experience on sedative-hypnotics persisted over two months after the withdrawal and that did not cross to that of narcotics.     

The role of sex differences in the effect of anabolics on the liver.

The effect of two anabolic steroids, norandrostenolone-phenylpropionate (Nerobolil) and norandrostenolone-decanoate (Retabolil) on the liver was studied in rats. Body weight, wet liver weight and the protein content of the liver homogenisates were found to increase under the effect of anabolic treatment, the most explicitely in females treated with Nerobolil. The function of the liver to metabolize hexobarbital, measured in vivo, is increased by a single dose of anabolic. The prolongation of treatment keeps on shortening hexobarbital anaesthesia only in females. Even 8 weeks after the end of treatment the effect is invariably lasting in females, in males it is not. Studies of the vaginal cycle cannot prove a decline of ovarial function. In females the hepatotropic effect of anabolic treatment, performed simultaneously with the chronic carbon tetrachloride lesion can be demonstrated. The liver weight and protein content are maintained on the control level. Under the effect of anabolic treatment the function to metabolize the effect of anabolic treatment the function to metabolize hexobarbital, which has been impaired by the lesion, remains near the level of the untreated animals. Our experiments support the observations of the inductive property of the steroids being parallel to their anabolic characteristics. Their catatoxic effect is pronounced in females. Nerobolil was found to be more advantageous from the point of view of both anabolic and hepatotropic effect. Our experiments do not suggest the possibility of liver damage during the administration of these two anabolics. The effect of the anabolics on the enzymatic induction may be of therapeutic value when adequate preparations are selected and sex differences as well as the character of the liver damage are taken into consideration.     

Protein-energy malnutrition and involuntary weight loss: nutritional and pharmacological strategies to enhance wound healing

Clinically significant involuntary weight loss (IWL) is defined as a loss of 4.5 kg or > 5% of the usual body weight over a period of 6 – 12 months, especially when progressive. Weight loss of > 10% of normal body weight is considered to represent protein-energy malnutrition (PEM). Despite progress in our understanding of the aetiology and pathophysiology of IWL and PEM, these conditions remain frequent and serious problems in several high-risk populations in both acute and long-term care facilities. In patients with IWL and PEM, nonhealing wounds signal a catabolic process that requires prompt nutritional intervention. Aggressive nutritional therapy that provides adequate protein, calories and micronutrients, combined with an anabolic agent such as oxandrolone, may provide the most optimal environment for restoration of lean body mass and body weight and in turn, promote wound healing. More research, however, is needed to define optimal nutritional and anabolic therapies for these patients given the associated high morbidity and cost of care.     

Protein-energy malnutrition and involuntary weight loss: nutritional and pharmacological strategies to enhance wound healing

Clinically significant involuntary weight loss (IWL) is defined as a loss of 4.5 kg or > 5% of the usual body weight over a period of 6 - 12 months, especially when progressive. Weight loss of > 10% of normal body weight is considered to represent protein-energy malnutrition (PEM). Despite progress in our understanding of the aetiology and pathophysiology of IWL and PEM, these conditions remain frequent and serious problems in several high-risk populations in both acute and long-term care facilities. In patients with IWL and PEM, nonhealing wounds signal a catabolic process that requires prompt nutritional intervention. Aggressive nutritional therapy that provides adequate protein, calories and micronutrients, combined with an anabolic agent such as oxandrolone, may provide the most optimal environment for restoration of lean body mass and body weight and in turn, promote wound healing. More research, however, is needed to define optimal nutritional and anabolic therapies for these patients given the associated high morbidity and cost of care.     

Antihypertensive responses elicited by central moxonidine in rats: possible role of nitric oxide

In the present study, we investigated the effects of pretreatment with NG-nitro-L-arginine methyl ester (L-NAME) (nitric oxide synthase inhibitor) injected intravenously (IV) on the hypotension, bradycardia, and vasodilation produced by moxonidine (alpha2-adrenergic/imidazoline receptor agonist) injected into the fourth brain ventricle (4th V) in rats submitted to acute hypertension that results from baroreflex blockade by bilateral injections of kynurenic acid (kyn, glutamatergic receptor antagonist) into the nucleus of the solitary tract (NTS) or in normotensive rats. Male Wistar rats (n=5 to 7/group) anesthetized with IV urethane (1.0 g kg(-1) of body weight) and alpha-chloralose (60 mg kg(-1) of body weight) were used. Bilateral injections of kyn (2.7 nmol 100 nL(-1)) into the NTS increased baseline mean arterial pressure (148 +/- 11 mm Hg, vs. control: 102 +/- 4 mm Hg) and baseline heart rate (417 +/- 11 bpm, vs. control: 379 +/- 6 bpm). Moxonidine (20 nmol microL(-1)) into the 4th V reduced mean arterial pressure and heart rate to similar levels in rats treated with kyn into the NTS (68 +/- 9 mm Hg and 359 +/- 7 bpm) or in control normotensive rats (66 +/- 7 mm Hg and 362 +/- 8 bpm, respectively). The pretreatment with L-NAME (25 micromol kg, IV) attenuated the hypotension produced by moxonidine into the 4th V in rats treated with kyn (104 +/- 6 mm Hg) or in normotensive rats (95 +/- 8 mm Hg), without changing bradycardia. Moxonidine into the 4th V also reduced renal, mesenteric, and hindquarter vascular resistances in rats treated or not with kyn into the NTS and the pretreatment with L-NAME IV reduced these effects of moxonidine. Therefore, these data indicate that nitric oxide mechanisms are involved in hypotension and mesenteric, renal, and hindquarter vasodilation induced by central moxonidine in normotensive and in acute hypertensive rats.     

Toxicity and carcinogenicity studies of Caramel Colour IV in F344 rats and B6C3F1 mice.

Caramel Colour IV, a type of caramel colour used in the manufacture of cola soft drinks, was evaluated for subchronic and chronic toxicity in rats, and carcinogenicity in Fischer-344 (F344) rats and B6C3F1 mice. In each of the studies, Caramel Colour IV was mixed with demineralized water and the solutions given to the animals ad lib. in the drinking fluid. The concentrations of Caramel Colour IV in the drinking fluid were adjusted periodically to achieve the desired caramel colour intake per kg body weight. In the range-finding studies, groups of 30 rats/sex were given Caramel Colour IV at levels of 0, 15, 20, 25 or 30 g/kg for 13 wk, and groups of 10 male rats were given levels of 0, 2.5, 5, 10 or 15 g/kg for 6 wk followed, for some dose groups, by a 2-wk withdrawal period, and then re-initiation of dosing for another 2 wk. In the rat chronic toxicity study, levels of Caramel Colour IV of 0, 2.5, 5, 7.5 or 10 g/kg were given to groups of 25 rats/sex for 12 months. The test groups in the rat and mouse carcinogenicity studies were composed of 50 animals/sex and each species was given the caramel colour at levels of 0, 0, 2.5, 5 or 10 g/kg for 24 months. In each of the studies, treated animals tended to have dose-related lower water consumption than controls. This was attributed to poor palatability of the drinking fluid, and was generally associated with decreased food consumption and body weights. Rats given caramel colour often had soft or liquid malodorous faeces although there were no treatment-related ante-mortem observations in mice. Blood biochemical changes in the rat (i.e. reduced blood urea nitrogen, alkaline phosphatase and total serum protein) appeared to be related to dietary influences and were not considered toxicologically significant. There were no treatment-related alterations in haematological variables or treatment-related differences in survival or in the incidence of benign or malignant tumours among treated and control groups and no toxicologically important pathological findings. On the basis of these studies, Caramel Colour IV was not toxic or carcinogenic in F344 rats or B6C3F1 mice. The highest dose level tested in the long-term studies (10 g/kg) was considered to be the no-observed-adverse-effect level (NOAEL).     

Anabolic activity of buclizine on rats

The antihistaminic drug buclizine hydrochloride, known to induce a weight gain in underweight patients, antagonized the catabolic effect of prednisolone in adult rats. This activity was estimated by nitrogen retention and compared with the activity of a known anabolic agent, ethylestrenol.     

用去势小鼠提肛肌-海棉球肌测定类固醇蛋白同化作用的方法

本文研究去势小鼠肾脏、提肛肌和海绵球肌对同化类固醇的反应敏感性,同时比较去势小鼠提肛肌、提肛肌-海绵球肌和大鼠提肛肌对17α-甲基睾丸素反应的差别.结果指出,去势小鼠的肾脏,无论从反应所需剂量,反应出现的快慢和反应持续时间的长短看,均系三种组织最不敏感者.提肛肌和海绵球肌对药物的敏感度大致相同.从去势小鼠和大鼠提肛肌及精囊反应上看,对药物的敏感度也大致相同.所不同者,大鼠提肛肌对药物的反应随剂量的增加而递增,不同剂量组的同化作用和雄性素样作用比值也较接近;而小鼠提肛肌的反应与剂量的关系不恒定,甚至大小颠倒,不同剂量组的比值变化也大.将去势小鼠提肛肌和海绵球肌合并后,则其反应即随剂量的增加而递增,不同剂量组的比值也很稳定.以上结果说明,用去势小鼠提肚肌-海绵球肌和精囊重量增加作为测定类固醇同化作用和雄性素样作用的指标是值得采用的.     

Toxicological evaluation of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-(methylaminocarbonyl)hydrazine (VNP40101M), a novel alkylating agent with potential antitumor activity, with intravenous administration in rats and dogs

These studies investigated the toxicological effects of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-(methylaminocarbonyl) hydrazine, VNP40101M, a novel alkylating antitumor agent, in animals. Sprague-Dawley rats (2-10/sex/time point at each dose) and Beagle dogs (1-3/sex/time point at each dose) were treated with VNP40101M (0 [vehicle], 1, 3, 10, and 20 mg/kg in rats and 0, 0.3, 1, and 3 mg/kg in dogs), given intravenously (IV, bolus via the tail or slow push via the cephalic or saphenous vein, respectively) once daily for 5 consecutive days. Clinical signs, mortality, body weight, clinical pathology, gross necropsy, organ weights, and histopathology were evaluated for as long as 43 days in rats and 50 days in dogs. In rats, the toxic doses were found to be at 10 and 20 mg/kg, which induced mainly pulmonary toxicity and mortality. The pulmonary toxicity was reflected by an increase in lung weight; clear, pink or red fluid within the thoracic cavity observed at necropsy; and histopathological evidence of alveolar edema, vascular congestion, alveolar histiocytosis, and vascular thrombi. Although some of these effects were observed in rats treated with 3 mg/kg, the incidence was low (approximately 7%-30%) and may be reversible (based on the time-dependent reduction in the magnitude of lung weight increases). Therefore, the maximum tolerated dose (MTD, or the maximum dose that did not induce significant toxicity or induced reversible toxicity) was > or = 3 mg/kg. VNP40101M at 1 mg/kg did not induce any toxicity, other than low incidence of alveolar edema (2/30 rats), and increased incidences of capillary ectasis/congestion and alveolar histocytosis (2-6/30 rats vs. 1/30-36 in control rats). Therefore, the low effect level (LOEL) is considered to be 1 mg/kg in rats when given IV for 5 days. In dogs, LOEL, MTD, and toxic dose levels were comparable (based on a body weight/surface area conversion) to those in rats, except for some gastrointestinal (GI) effects (i.e., red lesion in the ileum) observed at 0.3 mg/kg (equivalent to 1 mg/kg, or similar to the LOEL in rats) and the associated effects (slight body weight loss and inappetence). For dogs treated with 1 mg/kg (equivalent to approximately 3 mg/kg, or MTD, in rats), VNP40101M induced the same GI effects seen in dogs treated with 0.3 mg/kg of VNP40101M. Additionally, a transient reduction in white blood cell counts was also observed. Three mg/kg (equivalent to approximately 10 mg/kg, or toxic dose level, in rats) was toxic to dogs, as reflected by the poor clinical condition of these dogs, which subsequently required euthanasia. In conclusion, VNP40101M, when given IV once daily for 5 consecutive days, has a LOEL of 1 mg/kg, a MTD of 3 mg/kg, and toxic doses at > or = 10 mg/kg in rats. The primary toxicity of VNP40101M was pulmonary toxicity and mortality. Based on an interspecies body weight/surface area conversion, VNP40101M had comparable LOEL (0.3 mg/kg), MTD (1 mg/kg), and toxic doses (> or = 3 mg/kg) in dogs, except that dogs appeared to be more sensitive to the GI effects of VNP40101M.     

Cardiovascular Toxicities of Nandrolone and Cocaine in Spontaneously Hypertensive Rats

The outcome of concurrent abuse of cocaine and anabolic steroidsis largely unknown and merits investigation. The present studywas designed to determine whether an animal model could be developedfor investigation of the toxic responses to simultaneous administrationof cocaine and an anabolic steroid, nandrolone decanoate. Twenty-fourmale spontaneously hypertensive rats (SHR), all 7 weeks of age,were assigned randomly to four groups: (I) control, (2) cocaine,(3) nandrolone, and (4) cocaine plus nandrolone. Metabolic measurementsand indirect (tail-cuff) blood pressure and heart rate measurementswere per formed on all rats every 2 weeks. All drug treatmentgroups exhibited significantly (p <0.05) higher levels ofblood pressure after 6 weeks of treatment when compared to thecontrol group. Cocaine plus nandrolone group exhibited the lowestheart rate compared to other groups. Rats were euthanized at13 weeks of age, and different tissues were removed, blotteddry, and weighed. The kidney, levatorani muscle, and seminalvesicle (with prostate glands) weights in both nandrolone-receivinggroups were higher than those of the control and cocaine groups.Testicular weights of the cocaine plus nandrolone group wereless than those of the control and cocaine groups. Hearts werefixed in 10% buffered formaldehyde before myocardial dimensionmeasurements were performed. The nandrolone group showed increasedvertical ventricular diameters when compared to the controland cocaine groups. The nandrolone group also displayed highervertical ventricular circumferences when com pared to all theother groups. Finally, the cocaine plus nandro- lone group hadthe greatest ventricular weights (per 100 g body weight) andleft ventricular volumes. Myocardial inflammatory and fibroticchanges were significantly more evident in rats treated withnandrolone or cocaine plus nandrolone than in rats treated withvehicle or cocaine alone. The data suggest a potential for significantinteractions between pharmacological and toxic responses tococaine and nandrolone during the developing phase of hypertensionin SHR.     

The anabolic steroid methandienone targets the hypothalamic–pituitary–testicular axis and myostatin signaling in a rat training model

There is increasing evidence that the biological activity of myostatin (MSTN), a negative regulator of muscle growth, is affected by training but also anabolic steroids. In this study, we analyzed the effects of the frequently abused anabolic steroid methandienone (Md) on the hypothalamic–pituitary–testicular axis and androgen-sensitive tissues in intact rats performing a treadmill training to simulate the situation of abusing athletes. The anabolic effects were correlated with the expression of members of the MSTN signaling cascade. Md treatment resulted in a significant stimulation of anabolic activity of the levator ani muscle, which was further increased by training, while prostate and seminal vesicle weights decreased in conformance with hormone concentrations of LH and testosterone. In gastrocnemius muscle, mRNA expression of genes of the MSTN signaling cascade (MSTN, Smad7 and MyoD) was reduced by training but not after Md treatment, in soleus muscle MSTN and its inhibitors, follistatin (FLST) and Smad-7 were only affected after training in combination with Md treatment. In summary, our data demonstrate that Md treatment of intact rats results in anabolic effects which are enhanced in combination with physical activity. Interestingly, the anabolic activity on the levator ani was increased in combination with training, although the levator ani muscle was not specifically stimulated by our training protocol. In the m. gastrocnemius and soleus, the anabolic effects correlate with changes in the expression patterns of genes involved in MSTN signaling. Our data provide evidence that the decrease in the weight of androgen-sensitive sexual glands, observed after Md treatment, is caused by a suppression of endogenous testosterone synthesis. These observations provide new insights into the molecular mechanisms of the interaction between anabolic steroids, training and MSTN signaling during skeletal muscle adaptation.     

Evaluation of the acute and subchronic toxic effects in mice, rats, and monkeys of the genetically engineered and Escherichia coli cytosine deaminase gene-incorporated Salmonella strain, TAPET-CD, being developed as an antitumor agent

TAPET-CD, a genetically engineered Salmonella strain with chromosomal-incorporated cytosine deaminase (CD) gene, has been shown to selectively accumulate tumors, suppress tumor growth, and convert 5-fluorocytosine (5-FC, an antifungal agent) to the antitumor agent 5-fluorouracil (5-FU) in animals. The current studies investigated the safety of TAPET-CD, and TAPET-CD/5-FC combination, in animals. In C57BL/6 mice (n = 10 females/dose), the maximum nonlethal dose of TAPET-CD (intravenous [IV] bolus) was 1 x 10(6) colony-forming units (cfu)/mouse, or > 10,000 x that of wild-type Salmonella. In Sprague-Dawley rats (n = 4/sex/group), after treatment with 4 weekly cycles of TAPET-CD (an IV injection/cycle at 1 x 10(5), 3 x 10(5), 1 x 10(6), 3 x 10(6), or 1 x 10(7) cfu/rat on day 1) and 5-FC (per os twice daily [PO b.i.d.], 250 mg/kg on days 2-7/cycle), clinical signs and mortality were evaluated daily, body weight and clinical pathology weekly, and gross necropsy on day 29. No treatment-related toxicity, although occasional and mild clinical signs (e.g., dehydration), increased hepatic enzyme/function values and white blood cells, splenic enlargement, and bilateral red discoloration of the kidneys, were observed. In cynolmogus monkeys, Experiment 1 involved treatment with TAPET-CD (IV injection at 1 x 10(9) cfu/monkey). Clinical signs and mortality were evaluated daily, body weight weekly, and gross necropsy on days 2, 7, and 31 (1/sex/time point). Experiment 2 involved treatment with TAPET-CD (IV injection at 1 x 10(9) and 1 x 10(10) cfu/monkey in Groups 1 to 3 and Groups 4 to 6, respectively) on day 1 and 5-FC (PO b.i.d. at 250, 500, and 1000 mg/kg in Groups 1 to 3, and 500, 1500, and 0 mg/kg in Groups 4 to 6, respectively) on days 4 to 17 (n = 1/sex/group). Clinical signs and mortality were evaluated daily; body weight and clinical pathology on days 1, 2, 4, 14, and 18; body temperature on days 1, 4, and 18; ophthalmic examinations on days 3 and 17; and gross necropsy and histopathology on day 18. Experiment 1 indicated that TAPET-CD at 1 x 10(9) or 1 x 10(10) cfu/monkey was well tolerated, with only occasional mild clinical signs (i.e., emesis, vomiting, inappetance, loose/infrequent/absence of stool), increases in hepatic enzyme/function values, and splenic enlargement. Experiment 2 indicated that TAPET-CD/5-FC combination had a maximum tolerated dose (MTD) of 1 x 10(10) cfu/monkey for TAPET-CD and 500 mg/kg for 5-FC in monkeys. Supra-MTDs induced renal toxicity. In conclusion, TAPET-CD had a good safety profile (reflected by the extremely large amount of TAPET-CD needed to induce mortality or toxicity) in mice, rats, and monkeys. More adverse events were observed with TAPET-CD/5-FC combination when compared to TAPET-CD and these events were similar to the reported effects of 5-FU, suggesting the involvement of 5-FU.     

Design, synthesis, and in vivo SAR of a novel series of pyrazolines as potent selective androgen receptor modulators

A novel series of pyrazolines 2 have been designed, synthesized, and evaluated by in vivo screening as tissue-selective androgen receptor modulators (SARMs). Structure-activity relationships (SAR) were investigated at the R1 to R6 positions as well as the core pyrazoline ring and the anilide linker. Overall, strong electron-withdrawing groups at the R1 and R2 positions and a small group at the R5 and R6 position are optimal for AR agonist activity. The (S)-isomer of 7c exhibits more potent AR agonist activity than the corresponding (R)-isomer. (S)-7c exhibited an overall partial androgenic effect but full anabolic effect via oral administration in castrated rats. It demonstrated a noticeable antiandrogenic effect on prostate in intact rats with endogenous testosterone. Thus, (S)-7c is a tissue-selective nonsteroidal androgen receptor modulator with agonist activity on muscle and mixed agonist and antagonist activity on prostate.     

Effect of astragaloside IV on the embryo‐fetal development of Sprague–Dawley rats and New Zealand White rabbits

Astragaloside IV, a natural product purified from the Chinese medicinal herb Astragalus membranaceus (Fisch) Bge, is now being developed as a cardioprotective agent for treating cardiovascular diseases. In the present study developmental toxicity of astragaloside IV in Sprague–Dawley rats and New Zealand White rabbits was evaluated by intravenously administering astragaloside IV daily to rats at 0.25, 0.5 and 1.0 mg kg^?1 on gestation days 6–15, and to rabbits at 0.5, 1.0 and 2.0 mg kg^?1 daily on gestation days 6–18. Reproductive parameters were determined and fetuses were examined for external, visceral and skeletal malformations. There was significant difference in total weight gain during and after treatment between the control group and 1.0 mg kg^?1 group in rats. The percentage of fetal deaths in 0.5 and 1.0 mg kg^?1 rat groups was significantly higher than that of the control group, and higher in all treatment groups than in the control in rabbits. These results indicated that astragaloside IV was maternally toxic at 1.0 mg kg^?1 in rats and fetotoxic at a dose higher than 0.5 mg kg^?1, but devoid of teratogenic effects in rats and rabbits. In light of these findings it is perhaps prudent to advise caution to women who might use astragaloside IV to combat cardiovascular disease during pregnancy. Copyright © 2009 John Wiley & Sons, Ltd.     

Myosin heavy chain expression pattern as a marker for anabolic potency: desoxymethyltestosterone (madol), norandrostendione and testosterone repress MHC-IIb expression and stimulate MHC-IId/x expression in orchiectomized rat gastrocnemius muscle

Both 19-norandrostenedione (estr-4-ene-3,17-dione, NOR) and desoxymethyltestosterone (17alpha-methyl-5alpha-androst-2-en-17beta-ol, DMT or “madol”) are ‘designer steroids’ misused for doping purposes in the bodybuilding scene. We have previously characterized the pharmacological profile of madol and identified potential adverse side effects. The aim of this study was to investigate the anabolic potency of NOR, madol and the reference substance testosterone propionate (TP). Besides wet weight of the M.levator ani (LA), we examined the effects on muscle fiber type composition and myosin heavy chain (MHC) expression in the M.gastrocnemius (Gas) muscle as additional markers for anabolic potency. A Hershberger assay was performed, where orchiectomized (orchi) male Wistar rats were treated subcutaneously with NOR, madol, TP or vehicle control (all 1 mg/kg BW/day) for 12 days. Wet weights of the Gas, LA, prostate and seminal vesicle were examined to determine anabolic and androgenic effects. Fiber type composition of the Gas muscle was analyzed using ATPase staining, and MHC protein profiles were determined by silver stain and Western blot analysis. NOR and madol exhibited strong anabolic and weak androgenic potency by stimulating growth of the LA but not the prostate and seminal vesicle. Skeletal muscle fiber type composition characterized by ATPase staining was not significantly altered between the treatment groups, although there was a tendency toward lower levels of type IIB and increased type IIA fibers in all treatment groups relative to orchi. MHC protein expression determined by Western blot and silver stain analysis revealed that MHC IId/x was significantly up-regulated, while MHC IIb was significantly down-regulated in NOR, madol and TP groups relative to orchi. There were no significant differences for MHC IIa and MHC I expression between groups. Results suggest that the observed MHC expression shift could serve as a molecular marker to determine anabolic activity of anabolic steroids at least in skeletal muscle of orchi rats. The molecular mechanisms as well as the androgen-dependent regulation of MHC expression in intact skeletal muscle remain to be further investigated.     

Evaluation of subchronic inhalation toxicity of dimethyl disulfide in rats

This study was carried out to investigate the potential subchronic inhalation toxicity of dimethyl disulfide (DMDS) via whole-body exposure in F344 rats. Groups of 10 rats of each sex were exposed to DMDS vapor by whole-body exposure at concentrations of 0, 5, 25, or 125 ppm for 6 h/day, 5 days/wk for 13 wk. All the rats were sacrificed at the end of treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were examined. At 25 ppm, a decrease in the body weight gain, food intake, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and blood urea nitrogen (BUN) was observed in the males, but not in the females. However, at 125 ppm, a decrease in the body weight gain, food intake, and thymus weight and an increase in the weights of adrenal glands were observed in both genders. Serum biochemical investigations revealed a decrease in the AST, ALT, BUN, creatine phosphokinase (CPK), and triglyceride levels and an increase in the glucose level. In contrast, no treatment-related effects were observed in the 5 ppm group. The toxic potency of DMDS was slightly higher in males than that in females. In these experimental conditions, the target organ was not determined in rats. The no-observed-adverse-effect concentration (NOAEC) was found to be 5 ppm, 6 h/day for male rats and 25 ppm, 6 h/day for female rats.     

Evaluation of Subchronic Inhalation Toxicity of Dimethyl Disulfide in Rats

This study was carried out to investigate the potential subchronic inhalation toxicity of dimethyl disulfide (DMDS) via whole-body exposure in F344 rats. Groups of 10 rats of each sex were exposed to DMDS vapor by whole-body exposure at concentrations of 0, 5, 25, or 125 ppm for 6 h/day, 5 days/wk for 13 wk. All the rats were sacrificed at the end of treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were examined. At 25 ppm, a decrease in the body weight gain, food intake, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and blood urea nitrogen (BUN) was observed in the males, but not in the females. However, at 125 ppm, a decrease in the body weight gain, food intake, and thymus weight and an increase in the weights of adrenal glands were observed in both genders. Serum biochemical investigations revealed a decrease in the AST, ALT, BUN, creatine phosphokinase (CPK), and triglyceride levels and an increase in the glucose level. In contrast, no treatment-related effects were observed in the 5 ppm group. The toxic potency of DMDS was slightly higher in males than that in females. In these experimental conditions, the target organ was not determined in rats. The no-observed-adverse-effect concentration (NOAEC) was found to be 5 ppm, 6 h/day for male rats and 25 ppm, 6 h/day for female rats.