摘要:

AbstractThe effects of two pure chlorobiphenyls (2,4′,5‐trichlorobiphenyl and 2,2′,4,4′,5,5′‐hexachlorobiphenyl) on the reproductive capacity in female mice have been studied. The results obtained show that females given 0.5 mg 2,4′,5‐trichlorobiphenyl (TCB)/day or 0.5 mg 2,2′,4,4′,5,5′‐hexachlorobiphenyl (HCB)/day for six consecutive days, starting on the first day of pregnancy, have significantly lower frequencies of implanted ova than the control females, whereas the frequency of implanted ova does not differ either between females given 0.05 mg/day of TCB or HCB and the control females, or between females given TCB 0.05 mg/day or 0.5 mg/day and those given the corresponding dose of HCB. Females given 0.5 mg/day of TCB or HCB, respectively, also have significantly higher contents in the livers of cytochrome P‐450, on Day four of pregnancy, than the control females. The results also show that, under the experimental conditions used, neither the frequency of pregnancies nor the number of implanted ova per pregnant female differ significantly bet

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02211.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractThe effect of reserpine on the inhibition by (+)‐amphetamine and cocaine of the accumulation of3H‐dopamine (DA) in striatal slices and3H‐noradrenaline (NA) in slices of cerebral occipital cortex and heart atrium of rats and the release of the3H‐amines from these tissues were examined. Reserpine (5 mg/kg intraperitoneally) was injected 18 hours before the experiments. It was found that reserpine markedly enhanced thein vitropotency of amphetamine in the striatum and heart but only slightly in the cortex. After administrationin vivo(+)‐amphetamine was about 10 times more potent in reducing the amine accumulation in the cortex as in the striatum. Reserpine enhanced the effect in both regions. The inhibitory potency of cocainein vitrowas unchanged by reserpine in the striatum but was reduced in the cortex and heart. Reserpine did not change the inhibitory potency of desipramine in the cortex and heart. The release of the3H‐amines by (+)‐amphetamine was enhanced by reserpine in the striatum and heart but the small release produced in the cortex was not increased. The release produced by cocaine was similarly enhanced by reserpine but cocaine was much less active than (+)‐amphetamine. The results indicate that (+)‐amphetamine and cocaine inhibit the amine accumulation by dif

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02212.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractThe effect of parenteral administration of iron (dextran) on the number of asbestos fibers in the lungs, formation of asbestos bodies and the development of interstitial fibrosis was studied in guinea pigs exposed intratracheally to anthophyllite dust. The treatment did not accelerate, either qualitatively or quantitatively, the formation of asbestos bodies or retard the development of interstitial fibrosis. The number of naked asbestos fibers was also similar in anthophyllite‐inoculated animals to those similarly inoculated, but having had, additionally, a previous saturation with iro

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02213.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractThe metabolism of phenytoin was studied in 9 hyperthyroid and 7 hypothyroid patients before and after treatment with either antithyroid drugs or 1‐thyroxine. No difference in the half‐life, volume of distribution and metabolic clearance rate was found between untreated hyper‐ and hypothyroid subjects. Furthermore, normalisation of thyroid function test did not change the kinetic parameters of phenytoin. The results indicate that the well‐known correlation between thyroid function and antipyrine kinetics cannot be extrapolated uncritically to other drugs. It is concluded that no general rules are valid in the kinetics among different drugs in thyroid pathological conditions. Each drug must be evaluated by itself in different pathological con

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02214.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractIsoprenaline markedly relaxed rat uterine muscle and increased its content of cyclic AMP. The cyclic AMP concentration reached its highest value, about ten times the control after 3 min., after which it declined rather quickly at first but later more slowly. After 60 min. the cyclic AMP content reached twice the prestimulation value. The muscle remained relaxed all the time. If the incubation medium from the uterus treated with isoprenaline for 60 min. was added to a fresh muscle, a normal response was elicited. Addition of a new dose of isoprenaline to a muscle previously incubated with isoprenaline for 60 min. only gave a minimal rise in cyclic AMP after 3 min. The presence of catechol or corticosterone, which both decreased the inactivation of isoprenaline, showed no effect on the decrease of the isoprenaline‐stimulated cyclic AMP level. Nor could the decrease in the cyclic AMP response be prevented in the presence of GTP, F‐, adenosine or in Ca2+‐deflcient medium. The addition of theophylline and puromycin both lead to a slower decline of cyclic AMP content, but after 60 min. the value returned to near that seen after only isoprenaline. Our studies on isoprenaline‐induced desensitization of rat uterus have led us to the conclusion that the change in the capacity of the preparations to accumulate cyclic AMP may be a result of either changes in the β‐adrenoceptors or in the cycl

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02215.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractMale albino rats were exposed to butylcellosolve (n‐butoxyethanol). Collected urine was found to contain a characteristic metabolite, identified as n‐butoxyacetic acid by mass spectrometry. The identity of the compound was confirmed by synthe

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02216.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractSerum creatine phosphokinase (CPK) activity has been determined before and after intramuscular injection of lidocaine, diazepam or saline in humans and lidocaine, diazepam, digoxin and saline in pigs and rabbits. Two ml volume of each of the drugs was given to humans as well as to the experimental animals. No changes in CPK activity were found after saline in humans or rabbits but a minor increase was demonstrated in pigs. A marked increase of CPK activity was demonstrated after lidocaine or diazepam in humans and after lidocaine, diazepam or digoxin in pigs and rabbits.Post mortemexamination of the injection sites in the animals revealed extensive muscle tissue necrosis after lidocaine, diazepam and digoxin. No damage of the tissue was found after saline. CPK activity was also determined in rabbits receiving 2 ml of dilutions of diazepam in saline. The injection sites were examinedpost mortem. The CPK activity was increased in animals receiving 1:2 and 1:8 dilutions while a 1:20 dilution did not give rise to changes in the enzyme activity. The necrotic area diminished when diazepam was diluted and no pathological changes were found at the injection sites after the 1:20 dilution. Measuring the CPK activity in rabbits after an intramuscular injection seems to be a sensitive method for the determination of local toxicity.

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02217.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractAmongst heart, rectum and radula protractor muscles ofPila globosa, the heart showed a negative inotropic and negative chronotropic response while the rectum and radula protractor showed a positive tonotropic response to exogenously applied acetylcholine (ACh). The anti‐cholinesterase pesticide phorate substantially increased the response to ACh; at high doses it could also evoke cholinomimetic response from the heart. The anti‐cholinesterase property of phorate gradually increased with an increase in its contact period to the tissue. The extent of alteration in ACh response caused by prior treatment with low and high doses of phorate were very similar, indicating that the efficacy of phorate is by and large time‐dependent rather than dose‐dependent. The effect of phorate remained irreversible even after prolonged washing. The mode of action of phorate has been discussed in the light of the above f

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02218.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractMechanical and electrical responses of spontaneously contracting muscle strips from oestrogen dominated rabbit uterus were investigated by the sucrose gap method. The effects of isoprenaline and dibutyryl‐c‐AMP in the presence and absence of propranolol were tested. It has been shown previously that the β‐adrenoceptor agonist isoprenaline inhibits the spontaneously contracting uterus even in the presence of the β‐blocker propranolol. The rise in c‐AMP which is caused by isoprenaline, is, however, blocked by propranolol. The aim of this investigation was to study further the role of c‐AMP in the isoprenaline‐induced relaxation of the uterus.Isoprenaline (10‐6M) consistently abolished spikes and mechanical contractions, usually accompanied by hyperpolarization. Propranolol (3 × 10‐6M) markedly reduced the incidence of hyperpolarization, but did not affect the other actions of isoprenaline. Hyperpolarization does not seem to be a prerequisite for inhibition of uterine contraction. Dibutyryl‐c‐AMP mimicked the actions of isoprenaline. No positive evidence to support a hypothesis of a c‐AMP‐independent mechanism was found. Therefore a possible explanation of the results could be that isoprenaline increases c‐AMP in a small intracellular pool, mediating electrical and mechanical responses but

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02219.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractA method is described for the preparation and perfusionin vitroof isolated guinea pig lungs. 5‐HT is rapidly taken up from a perfusing solution by this organ (about 70% uptake). In the concentration range 10‐7to 5 × 10‐6M citalopram concentration dependently inhibited the uptake of 5‐HT by the lung preparation. Chlorimipramine inhibited the uptake of 5‐HT only by 40–50%, and the inhibition was not concentration dependent. The method used seems to be a reliable model for studying the up

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1978.tb02220.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY