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L Dorigotti

Publications and source records attributed to L Dorigotti.

28 records · Page 2Linked to original sources
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Renal function studies with cadralazine in conscious dogs: a comparison with hydralazine.

The effect of the antihypertensive vasodilator, cadralazine, on renal function in the conscious dog was compared to that of hydralazine using inulin and para-aminohippurate clearances. Both drugs were administered as intravenous bolus, at the dose of 1 mg/kg. As expected, hydralazine rapidly decreased mean blood pressure (from 110 to 89 mmHg), significantly increased heart rate (from 109 to 190 beats/min), markedly decreased urine volume (from 0.90 to 0.47 ml/min) and sodium excretion (from 101 to 45 microEq/min), and increased potassium excretion (from 28 to 53 microEq/min). Cadralazine displayed a similar activity on blood pressure and on heart rate, but differently from hydralazine, these effects appeared more slowly and were not accompanied by sodium and water retention. Hydralazine, but not cadralazine, caused a quick and transient decrease in glomerular filtration rate (from 55 to 40 ml/min), whereas both compounds increased renal plasma flow and reduced renal vascular resistance, renal extraction of para-aminohippurate and filtration fraction. Moreover, cadralazine increased plasma renin activity to a lesser extent than hydralazine, and this could explain the different effect on water and sodium excretion after acute administration of the two drugs.

Animals↗
PubMedDate not supplied

The effect of oxiracetam treatment on alterations of lipid metabolism in brain areas from spontaneously hypertensive rats.

It has been previously demonstrated that spontaneously hypertensive adult rats (SHR) develop severe hypertension and cerebrovascular lesions on drinking 1% NaCl from weaning and that the phospholipid metabolism in the whole brain is actively altered in these lesioned animals (SHR-NaCl) as compared to SHRs which drink only water and show only sporadic cerebrovascular lesions. We have now assayed the incorporation of labelled choline, ethanolamine, glycerol and arachidonic acid into the phospholipids from the cortex and hippocampus of SHR-water and SHR-NaCl at different time intervals from injection into the lateral ventricle of the brain. A noticeable decrease of both choline and arachidonate specific activity (SA) in the phospholipids was found in the cortex and hippocampus (where the effect is most evident) from SHR-NaCl. Based on the literature and the data obtained, we suggest that in SHR-NaCl brain areas a release of choline and fatty acid also occurs from choline glycerophospholipids as a consequence of the cerebrovascular lesions caused by NaCl treatment. Even if a relatively minor loss of the amount of the lipids studied is evident from our results as compared to their entire pool, this change may be quite important if it causes a modification of the lipidic bilayer in excitable membranes. In a parallel group of SHR-NaCl animals, treated with the nootropic drug oxiracetam, we observed that the metabolic utilization of the precursors was completely restored. These experimental data favour the hypothesis that oxiracetam is effective in stimulating the phospholipid metabolism rate at levels even higher than those of the SHR-water animals.

Animals↗
PubMedDate not supplied

Pharmacological studies on cadralazine: a new antihypertensive vasodilator drug.

Cadralazine is a new, orally effective antihypertensive vasodilator. Acute experiments indicate that the compound reduces blood pressure and increases heart rate. The doses which reduce systolic blood pressure by 25% (ED25) are very similar after oral and intravenous administration (spontaneously hypertensive rats, 1.8 mg/kg, p.o.; 2.3 mg/kg, i.v.; renal hypertensive dogs, 0.26 mg/kg, p.o.; 0.24 mg/kg, i.v.; awake normotensive dogs, 0.98 mg/kg, p.o.; 1.01 mg/kg, i.v.). By both routes the peak effect is reached after 3-5 hr, and the activity lasts more than 24 hr. Repeated oral administration in spontaneously hypertensive rats reduces blood pressure with no evidence of tolerance. Cadralazine reverses hypertensive responses to epinephrine in awake normotensive dogs and anesthetized cats. The inhibition of the increase in blood pressure induced by sympathetic outflow activation in pithed rats parallels the antihypertensive activity in onset, intensity, and duration. The effects of cadralazine are not due to a blockade of alpha-adrenoceptors, sympathetic neurons, or ganglionic transmission. Cadralazine has no antihistaminic, anticholinergic, or spasmolytic activity and no specific effect on behavioral tests. In comparison with hydralazine, cadralazine has less acute toxicity and a greater activity by the oral route.

Animals↗
PubMedDate not supplied

Effect of age and strain on cerebral phospholipid metabolism.

It has been demonstrated that spontaneously hypertensive adult rats (SHR) develop severe hypertension and cerebrovascular lesions on drinking 1% NaCl from weaning. Phospholipid metabolism is actively altered in these severely lesioned animals (SHR-NaCl) as compared to SHRs which drink only water and showed only sporadic cerebrovascular lesions. We have tested the incorporation of water soluble phospholipid precursors into the corresponding phospholipid from different brain areas, by injecting either a mixture of labeled glycerol and choline or glycerol and ethanolamine into the lateral ventricle of the brain of adult (4 months old) and senescent (12 months old) SHR-NaCl. The results were compared to those obtained from 4 and 12 months old Wistar normotensive rats. When adult normotensive rats were compared with adult hypertensive rats (4-SHR-NaCl) incorporation was found to decrease in some areas according to the precursors injected. Similar results were obtained from 12 month old normotensive Wistar rats that, however, showed a decrease in phospholipid biosynthesis in all the area tested. Interestingly, no significant differences of incorporation rate were found between 12 month old normotensive and 12 month old hypertensive rats.

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