Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0278080 (physical dependence)
 1,658 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A comparison of several methods for developing physical dependence to morphine was made. Male Sprague-Dawley rats were treated with morphine-admixed food (drug-admixed food, DAF; 0.5 and 1 mg/g food), morphine slow release emulsion (SRE; 75, 100 and 150 mg/kg) and morphine (75 mg) pellets. In the SRE and pellet methods, the typical signs of morphine toxicity, such as catatonia, exophthalmos and shallow respiratory movements, were observed 15-20 min after the treatment and these signs were maintained for 14-18 hr. In rats treated with SRE and pellets, plasma morphine levels reached a maximum 1 day after the morphine treatment, and subsequently decreased, while plasma morphine levels in rats treated with DAF increased treatment period-dependently. Withdrawal signs precipitated by naloxone (3 mg/kg, sc) in rats treated with DAF, SRE and pellets were characterized by loss of body weight, shaking, vocalization, diarrhea, ptosis, tooth-chattering, nose bleed, salivation and lacrimation. Naloxone-precipitated withdrawal signs reached a maximum 1-2 days after treatment with SRE and pellets, and were correlated with the duration of DAF treatment. Rats treated with DAF, SRE (150 and 225 mg/kg) and pellets for 3 days, manifested loss of body weight, diarrhea etc. after the morphine withdrawal. Maximum body weight loss in each group was 7-10% at 1-2 days after the morphine withdrawal. It was thus, concluded that physical dependence on morphine can be induced rapidly by these three methods. However, the SRE and pellet methods induced morphine toxicity and it was difficult to maintain physical dependence on morphine in these rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Comparison of three methods of inducing physical dependence to morphine in rats using short-term medication]. 654 77

The preference and physical dependence for morphine, changes in gross behaviors and growth were investigated in the offspring of pregnant rats treated with morphine. Six groups (A-F) of the pregnant rats were treated with morphine by DAF (drug-admixed food) method for the following periods. No morphine-treatment was received in group A, treatment form the beginning of pregnancy (day 0) to weaning in group B, from day 0 to day 14 in group C, from day 15 to day 21 in group D, from day 0 to weaning in group E (the same of B), and no treatment in group F. The pups of group E were fostered to maters of group F, and pups of group F, and pups of group F were to maters of group E. The preference rate for morphine in pregnant rats increased significantly in comparison with of non-pregnant rats. Weanling rates of group B, C, D and E decreased significantly when compared with that of group A. The pups of maternal rats treated with morphine showed hyperactivity and vocalization. These symptoms were considered to be resulted from the withdrawal signs. The withdrawal signs may produce the decrease in the weanling rates. There was no difference in body weight gains in the offspring between group A and B. Preference rate for morphine in the offspring of group B was lower than that of group A. It may be due to an enhanced susceptibility to morphine in group B. However, no marked change in intensity of physical dependence on morphine was detected in the offspring between group A and B.
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PMID:[Effects of morphine on the successive generation]. 689 47

The purpose of the present paper is to investigate the effect of combined treatment of morphine and ethanol on preference for morphine or ethanol and morphine dependence formation. Rats were treated with morphine by DAF (drug-admixed food; 0.5 and 1 mg/g food) method or subcutaneous injection (20-100 mg/kg body weight), and/or treated with ethanol solution (5 and 10 w/w %) or oral administration (2.5 g/kg body weight). There were no effects of chronic treatment of ethanol and morphine on preference for morphine and ethanol, respectively. While, preference for morphine did not increase and preference for ethanol enhanced markedly in rats chronically treated with morphine and ethanol. Effect of chronic ethanol treatment on morphine physical dependence formation in rats was evaluated by body weight loss after morphine withdrawal, and the weight loss significantly attenuated and diarrhea was suppressed in comparison with morphine alone group. These results indicated that preference for morphine and morphine physical dependence formation were reduced when rats were chronically treated with ethanol during chronic morphine treatment, and that preference for ethanol was enhanced.
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PMID:[Effects of combined administration of morphine and ethanol on drug selecting behaviors and the development of drug dependence]. 689 49

The new cognition-enhancing agent nefiracetam (N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide, DM-9384, CAS 77191-36-7) was assessed for dependence liability in rats using the DAF (drug admixed food) method and an intravenous self-administration system. In the physical dependence test, nefiracetam and codeine phosphate were administered to rats mixed with food for 43 days in a gradually increasing dosage schedule, followed by feeding a drug-free normal diet to detect signs of withdrawal. After the withdrawal, rats in the nefiracetam treated groups showed no withdrawal symptoms (e.g. body weight loss) and exhibited greater body weight gains than control. On the other hand, rats in the codeine phosphate treated group showed overt withdrawal symptoms (e. g. soft stool, diarrhea, vocalization) and a significant body weight loss, suggesting development of physical dependence on the drug. It was concluded that nefiracetam did not possess physical dependence liability in rats. In the reinforcement liability test, through an indwelling cannula implanted into the right jugular vein rats were allowed to self-administer nefiracetam, morphine hydrochloride or pentobarbital for 14 days. Saline was administered to negative control animals for the same period. The daily frequency of self-administration increased progressively with time in rats of the morphine hydrochloride and pentobarbital groups. In the nefiracetam groups, it remained comparable to or was even lower than that in the saline control group. When compared with the saline control, the group mean frequency of self-administration showed a tendency to be small for nefiracetam, whereas the morphine hydrochloride and pentobarbital showed greater frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Drug dependence study of the new cognition-enhancing agent nefiracetam in rats. 801 97