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C Carpi

Publications and source records attributed to C Carpi.

At least 19 recordsLinked to original sources

Vascular protection of lacidipine in salt-loaded Dahl-S rats at nonsustained antihypertensive doses.

The aim of this study was to characterize the antihypertensive and vasoprotective properties of lacidipine in salt-loaded Dahl-S rats, a suitable animal model of malignant hypertension. After 9 weeks of a high (8%) sodium chloride (NaCl) diet, 80% of the untreated Dahl-S rats died (20% survival rate) whereas a 100% survival rate was observed with chronic treatment with lacidipine at doses of 0.1 (equivalent to the recommended dose in humans), 0.3, 1, and 10 mg/kg once daily by gastric gavage. The most interesting results included the following: (a) Only the highest dose tested (10 mg/kg once daily) was able to control the increase in blood pressure, which was measured 24 h after the preceding administration of drug, yet a 100% survival rate was maintained. (b) There appeared to be prevention of brain lesions, which is very likely the cause of the survival of all of the lacidipine-treated rats in this study. (c) A clear dose-related vascular protection was observed in other tissues. In conclusion, lacidipine protects against the vascular damage and concomitant increase in mortality of salt-loaded Dahl-S rats even at doses that do not adequately control the development of hypertension.

Administration, Oral↗

Lacidipine: a calcium antagonist with potent and long-lasting antihypertensive effects in animal studies.

Lacidipine, currently being evaluated as a once-daily antihypertensive agent, acted as a calcium entry blocker on rabbit ear artery (pA2 = 9.4) with a markedly slower onset of action than that of nitrendipine; this effect was not reversed after 9 h of drug washout. Calcium entry blocker activity was also evaluated on nonvascular smooth muscles: Lacidipine showed a more pronounced vascular selectivity than nitrendipine; for both drugs, concentrations required to induce negative inotropic effects in guinea pig ventricular strip were approximately 100 times higher than concentrations needed to antagonize calcium contraction in vascular smooth muscle. In spontaneously hypertensive rats (SHR), by the tail-cuff method, lacidipine (ED25 = 0.35 mg/kg orally, p.o.) proved approximately 30 times more potent, slower in onset, and longer-acting than nitrendipine in reducing blood pressure. These features were confirmed in chronically implanted SHR after oral and intravenous (i.v.) administration (ED25 = 0.19 mg/kg p.o. and 0.006 mg/kg i.v.). A short-lasting tachycardia was detected with both drugs. No evidence of acquired tolerance emerged after repeated oral administrations over a 3-week period. Lacidipine induced a natriuretic effect in saline-loaded SHR at antihypertensive doses. In renal hypertensive dogs, lacidipine proved more potent (three to seven times), slower in onset, and longer-lasting than nitrendipine after p.o. (ED25 = 0.22 mg/kg) and i.v. (ED25 = 0.004 mg/kg) administrations.

Animals↗

Effect of acetyl-L-carnitine treatment on some behavioural, histochemical and histological parameters of methylazoxymethanol microencephalic rats.

The effect of methylazoxymethanol (MAM) administration at the 15th gestational day on some behavioural and morpho-functional parameters of rat brain was investigated. The effect of a 13-15-day treatment of acetyl-L-carnitine on the same parameters was also assessed. MAM microencephalic rats showed a significant impairment in water-maze and pole-climbing tests. The histochemical reactivity of the enzyme NADH2-tetrazolium reductase (NADHR) at the level of frontal and occipital cortex, neostriatum and hippocampus was remarkably reduced. Also cholinacetyltransferase (ChAT) immunoreactivity within nerve cell bodies of the pontine tegmentum was decreased in MAM-treated animals. On the contrary, acetylcholinesterase (AChE) reactivity was increased in all the investigated brain areas with the sole exception of the neostriatum. Nissl reactivity was decreased in the cytoplasm of the pyramidal neurons of the frontal cortex and hippocampus, and slightly increased in the cytoplasm of pyramidal neurons of the occipital cortex of MAM microencephalic rats. Acetyl-L-carnitine treatment improved the behaviour of microencephalic rats in water-maze and pole-climbing tests. Moreover the substance stimulated NADHR reactivity in the cerebral cortex and hippocampus as well as ChAT immunoreactivity in the cytoplasm of neurons of the raphe pontine nuclei. Pharmacological treatment reduced AChE reactivity in the cerebral cortex and the hippocampus, and improved the pattern of Nissl reactivity within all brain areas examined.

Acetylcarnitine↗

Effect of acetyl-L-carnitine on conditioned reflex learning rate and retention in laboratory animals.

The aim of the study was to evaluate the effects of acetyl-L-carnitine on learning and/or memory processes in laboratory animals. In the water maze test, acetyl-L-carnitine, given intraperitoneally at doses ranging from 0.3 to 100 mg/kg, improved performances in both mice and rats. In the latter the drug also proved active when administered orally in the 3-100 mg/kg dosage range. In the pole climbing test in the rat, acetyl-L-carnitine at doses ranging from 0.03 to 10 mg/kg i.p. increased the conditioned reflex learning rate. In the passive avoidance test in the rat, significant increases in retention were observed after treatment with acetyl-L-carnitine at doses ranging from 1 to 30 mg/kg i.p. In the passive avoidance plus electroconvulsive shock test in the mouse, acetyl-L-carnitine antagonized amnesia at doses ranging from 0.1 to 3 mg/kg i.p.

Acetylcarnitine↗

Detection of active Epstein-Barr infection in pregnant women.

Sera taken from pregnant patients and their newborns at delivery were examined for evidence of primary or reactivated Epstein-Barr virus infection. Of 102 women, 37 showed serological signs of reactivated and two signs of primary infection. A mild congenital defect was observed in association with one of the two cases of maternal primary infection. Infants of mothers with reactivated infections remained healthy during the one year follow-up after birth.

Adolescent↗

Serological screening for the prevention of transfusion-acquired cytomegalovirus infection.

The presence of antibodies against cytomegalovirus (CMV)-induced immediate-early antigens (IEA), early antigens (EA) and late antigens (LA) was sought in 500 healthy blood donors. Antibodies to late antigens were detected in 76% and antibodies to immediate-early and early antigens were detected in 9.6% and 10.2%, respectively. The incidence of antibodies to CMV-induced immediate-early and early antigens increased with age, was higher in females than in males and was related to high values for antibodies against CMV late antigens. Since antibodies to CMV immediate-early and early antigens are significantly associated with active CMV infection, criteria for choosing blood samples unlikely to transmit infective CMV are evaluated.

Adult↗

Rapid detection of antibodies against cytomegalovirus induced immediate early and early antigens by an enzyme linked immunosorbent assay.

An enzyme linked immunosorbent assay (ELISA) for detecting antibodies against cytomegalovirus induced immediate early antigens and early antigens was developed using purified nuclear antigens and was compared with the indirect immunofluorescence test. The tests were comparable in their ability to detect positive and negative sera, and antibody titres determined by both assays were similar. The use of ELISA for the detection of antibodies against cytomegalovirus induced immediate early and early antigens is advocated in diagnostic and research laboratories.

Antibodies, Viral↗

Effects of pildralazine alone and in combination on severe hypertension and cerebrovascular lesions in saline-drinking spontaneously hypertensive rats.

The efficacy of long-term treatments with the vasodilator antihypertensive pildralazine alone and in combination with propranolol or dihydrochlorothiazide in preventing blood pressure increase and cerebrovascular lesions in saline-drinking spontaneously hypertensive rats (SHR) was evaluated. Groups of 20-40 animals were treated daily for 13 weeks. At the end of the experiments the brains were examined histologically and vascular lesions, ranging from arterial wall damage to cerebral infarction, were checked. In the control groups (n = 60), systolic blood pressure gradually rose to over 200 mmHg, and about 74% of the animals had lesions. Pildralazine at a dose of 1 mg/kg p.o. significantly inhibited the onset of severe hypertension; the combination of pildralazine with moderately effective doses of propranolol (10 mg/kg p.o.) or dihydrochlorothiazide (5 mg/kg p.o.) completely prevented the blood pressure increase. When blood pressure control was achieved, the incidence of cerebrovascular lesions was also significantly reduced.

Animals↗

Serum antibody profile against herpesviruses in renal transplant recipients.

Forty-eight renal allograft recipients who had received a kidney graft 2 months to 8 years previously, were followed for the presence of serum antibody against Cytomegalovirus (CMV), Epstein-Barr virus (EBV), Herpes simplex virus (HSV), and Varicella-Zoster virus (VZV). These investigations were performed over a 6 months period and in at least two serum samples from each patient, obtained at intervals of 2-3 months. The presence of serological signs of recent or active infection were observed in 31 patients for CMV, in 22 patients for EBV (18 patients were positive both for CMV and EBV) and only in 3 patients for HSV, while no patients showed serological signs of recent or active infection by VZV.

Adolescent↗

3-Hydrazinopyridazine derivatives as inhibitors of pyridoxal-phosphate dependent enzymes.

A series 3-hydrazinopyridazine derivatives with anti-hypertensive properties was studied as inhibitors of pyridoxal-phosphate dependent enzymes. All the compounds with a free hydrazino group were found to be strong inhibitors in vitro. In vivo inactive compounds became active at doses which exert a hypotensive action. The significance of this inhibition is discussed.

Amine Oxidase (Copper-Containing)↗

Semisynthetic beta-Lactam antibiotics. II. Penicillins from alpha-hydrazinoarylacetic acids.

A number of penicillins (2) have been synthesized from the alpha-hydrazinoarylacetic acids (4) via the activated chloride hydrochlorides (5) or via the mixed anhydride of the corresponding N2-benzyloxycarbonyl derivatives (6). The penicillins, 2b, e, j, show good activity against gram-positive and gram-negative bacteria and enhanced penicillinase resistance in comparison with ampicillin.

Acetates↗

Quinoxaline studies. 23. Potential antimalarials. Substituted 5,8-dimethoxy-6-[N-(omega-dimethylaminoalkyl)amino]quinoxalines were prepared: the first series with identical 2,3-substituents H, CH3, C6H5, C6H4-4-Cl, and CH2C6H5; and the second with identical styryl groups CH=CHC6H5, CH=CHC6H4-4-Cl, CH=CHC6H3-3,4-Cl2, CH=CHC6H4-4-F, CH=CHC6H4-4-CF3, and CH=CHC6H4-4-NO2. None of the substances possessed antimalarial activity; several were toxic at highest dosage levels.

3-Hydrazinopyridazines substituted in position 6 with a primary amine, secondary amine, or an alkoxy group were synthesized and screened for antihypertensive activity. In general, the 6-dialklamino derivatives are the most active; the (2-hydroxypropyl)methylamino chain provides the best combination of high antihypertensive activity and toxicity.

Animals↗