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1.
A characteristic and reproducible sign of narcotic withdrawal is the naloxone induced increase in arterial pressure. In morphine-dependent rats allowed to undergo spontaneous withdrawal (6-24 h) and then transected at the spinal C-1 level, arterial pressure was maintained at a significantly higher level than either spinal-transected nondependent controls or morphine-dependent, spinal-transected rats pithed from C-1 to L-4. These findings indicate that the morphine-dependent spinal cord, independent of supraspinal influences, is able to exhibit an autonomic component of spontaneous withdrawal.  相似文献   

2.
Summary Five unusual amino acids were identified as antimutagens against spontaneous mutation ofSalmonella typhimurium TA100: L-azetidine-2-carboxylic acid (1) from Liliaceae plants, -(methylenecyclopropyl)glycine (2) fromLitchi chinensis seeds, and 2-amino-4-methylhex-5-ynoic acid (3), hypoglycin A (4), and (2S, 4R)-2-amino-4-hydroxyhept-6-ynoic acid (5) fromEuphoria longana seeds. The absolute stereochemistry of5 was determined by its chiral synthesis from L-allylglycine, proving that5 is the C-4 epimer of the amino acid previously isolated from dried longan seeds.This work was partly supported by a Grant-in-Aid form the Ministry of Education, Science, and Culture, Japan, No. 57740283 (to HK).  相似文献   

3.
2 new 4-trifluoromethylimidazole derivatives were found which lowered mean arterial pressure in renal and spontaneously hypertensive (SH) rats by the oral route. In SH rats, compounds A and B were 0.1 and 0.3 times, respectively, as potent as hydralazine. No tolerance development was observed in SH rats with either compound over a 1-week period. In anesthetized dogs, both compounds lowered arterial pressure and peripheral vascular resistance but increased cardiac output. By intraarterial administration, both compounds increased femoral arterial blood flow. These findings represent discovery of a new class of vasodilator durgs.  相似文献   

4.
Summary 2 new 4-trifluoromethylimidazole derivatives were found which lowered mean arterial pressure in renal and spontaneously hypertensive (SH) rats by the oral route. In SH rats, compounds A and B were 0.1 and 0.3 times, respectively, as potent as hydralazine. No tolerance development was observed in SH rats with either compound over a 1-week period. In anesthetized dogs, both compounds lowered arterial pressure and peripheral vascular resistance but increased cardiac output. By intraarterial administration, both compounds increased femoral arterial blood flow. These findings represent discovery of a new class of vasodilator drugs.Deceased, May 31, 1978.  相似文献   

5.
L F Obika 《Experientia》1987,43(8):880-883
The blood pressure and heart rate responses to intravenous dopamine infusion at 2.5, 5.0 and 10.0 micrograms.min-1 X 100 g-1 were studied in conscious and pentobarbital-anesthetized Sprague-Dawley rats. In the conscious rats, dopamine caused a significant dose-related increase in the mean arterial blood pressure which was abolished in the anesthetized rats. The heart rate increased significantly only at the highest dose infused. The responses to equipressor doses of noradrenaline (40 ng.min-1 X 100 g-1) and phenylephrine (1.0 micrograms.min-1 X 100 g-1) were also suppressed in the anesthetized rats. The results suggest that pentobarbital anesthesia depresses the blood pressure response to dopamine infusion in the rat through a depression of activation of alpha-adrenoceptors.  相似文献   

6.
Summary The blood pressure and heart rate responses to intravenous dopamine infusion at 2.5, 5.0 and 10.0 g·min–1·100 g–1 were studied in conscious and pentobarbital-anesthetized Sprague — Dawley rats. In the conscious rats, dopamine caused a significant dose-related increase in the mean arterial blood pressure which was abolished in the anesthetized rats. The heart rate increased significantly only at the highest dose infused. The responses to equipressor doses of noradrenaline (40 ng·min–1·100 g–1) and phenylephrine (1.0 g·min–1·100 g–1) were also suppressed in the anesthetized rats. The results suggest that pentobarbital anesthesia depresses the blood pressure response to dopamine infusion in the rat through a depression of activation of alpha-adrenoceptors.16 June 1986  相似文献   

7.
Summary Two new-adrenoceptor blocking drugs with acute antihypertensive and positive inotropic effects are described: Compound A (2-[4-(3-tert. butylamino-2-hydroxypropoxy)phenyl]-4-trifluoromethylimidazole) and MK-761 (2-(3-tert. butylamino-2-hydroxypropoxy)-3-cyanopyridine hydrochloride). In SH rats both compounds, given orally, lowered arterial pressure and were more potent than hydralazine. The antihypertensive effect of compound A but not of MK-761 was antagonized by timolol. Both compounds had positive inotropic activity on cat heart papillary muscles; these effects were antagonized by timolol. The pretreatment of animals with reserpine greatly reduced the positive inotropic effect of MK-761 but not of compound A. The acute antihypertensive and positive inotropic effects of compound A are likely to be at least partially due to stimulation of-adrenoceptors, e.g. intrinsic sympathomimetic activity. The effects of MK-761 on the same parameters appear to be mediated by different mechanisms.  相似文献   

8.
Chromogranin A (CHGA) is ubiquitously expressed in secretory cells of the endocrine, neuroendocrine, and neuronal tissues. Although this protein has long been known as a marker for neuroendocrine tumors, its role in cardiovascular disease states including essential hypertension (EH) has only recently been recognized. It acts as a prohormone giving rise to bioactive peptides such as vasostatin-I (human CHGA1–76) and catestatin (human CHGA352–372) that exhibit several cardiovascular regulatory functions. CHGA is over-expressed but catestatin is diminished in EH. Moreover, genetic variants in the promoter, catestatin, and 3′-untranslated regions of the human CHGA gene alter autonomic activity and blood pressure. Consistent with these findings, targeted ablation of this gene causes severe arterial hypertension and ventricular hypertrophy in mice. Transgenic expression of the human CHGA gene or exogenous administration of catestatin restores blood pressure in these mice. Thus, the accumulated evidence establishes CHGA as a novel susceptibility gene for EH.  相似文献   

9.
Summary Follwing withdrawal from chronic barbital administration, 6-hydroxydopamine pretreated rats show a greater number and an earlier onset of spontaneous convulsive seizures than do rats pretreated with the saline-ascorbic acid vehicle.Supported by NIMH Grant No. 5 RO1 DA00755-02.Recipient of Research Scientist Development Award, No. 1 KO2 MH00028-01.  相似文献   

10.
Summary The new phenolic bisbenzylisoquinoline alkaloid (+)-baluchistine, found inBerberis baluchistanica Ahrendt (Berberidaceae), has been assigned structure1. O-Methylation using ethereal diazomethane yields (+)-obaberine (2). Baluchistine is the 1 alkaloid of the oxyacanthine-berbamine group to incroporate a free phenolic function at C-6.this project was supported by NIH research grant CA-11450, awarded by the National Cancer Institute, PHS/DHEW.  相似文献   

11.
Summary A study was undertaken on the variations of the redox potential level produced by streptomycinin vitro andin vivo. We have been able to show that, owing to an oxidative effect, streptomycin produces an increase of the redox potential level. This oxidative effect varies in degree according to the condition of the patient.We also found that in the blood and in the spinal fluid of patients suffering from tubercular meningitis factors are present which inhibit the action of streptomycin.The results of our findings lead to the conclusion that the dose of streptomycin must be varied according to the condition of the patient if the constant level required for an efficient therapy is to be maintained in the blood and in the spinal fluid.  相似文献   

12.
Summary In contrast to the female, the adult males ofLytta vesicatoria (Coleopt. Meloidae) produced radioactive cantharidine on injection with14C-1-acetate and14C-2-mevalonate solutions. A partial degradation of the cantharidine showed that in the acetate experiment approximately of the activity occurred at C atoms 2 + 3 whereas with mevalonate approximately of the activity was at C atoms 8 + 9 and at C atoms 10 + 11. These results show that cantharidine is not formed by a tail to tail linkage of 2 isoprene units.

Wir danken dem Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung für die Unterstützung dieser Arbeit, Herrn Dr.J. Würsch (Physikalisch-chemische Abteilung der Firma F. Hoffmann-La Roche & Co. AG, Basel) für14C-2-Mevalolacton und unserer mikroanalytischen Abteilung (LeitungH. Frohofer) für die Aktivitätsbestimmungen.  相似文献   

13.
Summary Four alkaloids have been isolated from the skin gland of the Feuer- and Alpensalamander (Salamandra maculosa andatra Laur.). The structure, stereochemistry and absolute configuration of the principal alkaloid, samandarin, have been elucidated by chemical, optical, and X-ray-crystallographic methods. The basic structure of samandarin is derived from 5-androstan by the insertion between C-2 and C-3 of ring A of an NH group which, along with an oxygen bridge between C-1 and C-3, constitutes an oxazolidine ring; at C16 there is a-hydroxyl group. By virtue of its origin and constitution samandarin occupies a unique position among alkaloids.

Nach der am 15. Juni 1960 in der Aula der Universität Zürich gehaltenen zweitenPaul-Karrer-Vorlesung. Der Vortrag ist zum Teil gekürzt, Ergebnisse der letzten Zeit sind in die vorliegende Fassung eingearbeitet worden.  相似文献   

14.
Résumé A partir des racines deRuta graveolens, on a isolé un alcaloide acridonique, 1-hydroxy-N-méthyl-acridone, dont la biosynthèse doit comporter une élimination réductive des OH-groups en C-1 et C-3.  相似文献   

15.
Summary Radioactivity in the fetal plasma 1 h after maternal injection of14C-4-corticosterone or14C-4-estradiol-17 on day 21 of gestation was markedly higher than that 1 h after injection on day 22. Radioactivity in the maternal plasma was not different on these 2 days. The results suggest that the placental permeability to steroids from the mother to the fetus declines toward the end of gestation in the rat.Acknowledgment. We are indebted to Professor Tatsuo Imori (Department of Veterinary Surgery, College of Agriculture, University of Osaka Prefecture) for his valuable suggestions during the course of this study.  相似文献   

16.
Summary A multiplicity of types of neurosecretory cell (NSC), and uniformity in the numbers occurring in medial, lateral, posterior and tritocerebral groups, have been observed inP. ricini. 3 types of cells A, B and C, with their subtypes (A-1, A-2, A-3; B-1, B-2; C-1 and C-2) have been reported. Only B-cells increase in numbers during post-embryonic development. Others (A and C) remain constant throughout development. Abnormal staining behaviour of A-cells has also been reported.Acknowledgements. We are grateful to Prof. S.D. Misra for the facilities and to the UGC, New Delhi, for sanctioning a grant No. F. 23-781/78 (SR II) dated 27.4.78 to Dr V.B. Awasthi, which is gratefully acknowledged.  相似文献   

17.
Summary Using tritium labelled substrates it is shown that in the rearrangement of (S) --lysine to 3,5-diaminohexanoic acid catalysed by-lysine mutase a stereospecific hydrogen migration from C-5 to C-6 of the substrate occurs. When the reaction is carried out in the presence of [5-3H]-coenzyme B12, the heavy isotope is transferred both to C-6 of 3, 5-diaminohexanoate and to C-5 of-lysine. In the latter the labelled atom occupies the same diastereotopic position as the H atom that is transferred to C-6 of the product.  相似文献   

18.
Summary Serum testosterone concentrations were measured in adult male Sprague-Dawley rats. A significant circadian testosterone rhythm (p<0.01) was found with peak values at 10.00 and 13.00 h.Supported in part by NIH, NCI Grant No. CA 15062 and NIH, NIAMDD Grant No. 5 RO1 AM11376.The authors would like to acknowledge the excellent technical assistance of Ms.Kris Strom.  相似文献   

19.
Biological activities of pure prostaglandins   总被引:4,自引:0,他引:4  
E W Horton 《Experientia》1965,21(3):113-118
Prostaglandins, the hydroxy unsaturated C20 fatty acids, are found throughout the body and have an equally wide range of biological activities. Prostaglandins are known to: 1) stimulate uterine contraction; 2) inhibit spontaneous contraction of the rabbit uterus; 3) inhibit the respiratory smooth muscle of different animals; 4) lower systemic arterial blood pressure when injected intravenously; 5) stimulate contractions in isolateral segments of intestinal smooth muscle of most species investigated; 6) produce transient sedation when intravenously injected in cats, and 7) inhibit lipolysis induced by catechal amines, corticotrophin, glucagon and thyroid stimulating hormone. The inhibitory and excitatory effects of prostaglandins may each have a physiological importance at different sites. Current state of knowledge of the distribution, metabolism and actions of the prostaglandins is still fragmentary. The functional significance of the prostaglandins is yet to be determined.  相似文献   

20.
Summary Brianolide (1), a new antiinflammatory diterpenoid of the briarein class, possessing a substituent at C-12 (R), has been isolated from the Okinawan gorgonianBriareum sp. Its structure has been established from spectral data in conjunction with a single crystal X-ray analysis.  相似文献   

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