PubMed Health⌕ Search

Biomedical subjects

N Basso

Publications and source records attributed to N Basso.

At least 91 records · Page 5Linked to original sources
PubMed1987

Changes in the renin-angiotensin-aldosterone system in rats of both sexes submitted to chronic hypobaric hypoxia.

The effect of moderate chronic hypobaric hypoxia (CHH) on the renin-angiotensin-aldosterone system has been analysed in male and female intact and castrated rats. The experimental animals were submitted to a simulated altitude of 4,400 m during ten weeks. Half of the experimental and half of the control animals were castrated at three weeks of age. Arterial pressure (AP) was measured once a week during the whole experimental period. Blood samples were obtained by decapitation at the end of the study. Red cell volume, plasma renin activity (PRA), plasma angiotensinogen (Ao) and aldosterone concentration (ALDO) were determined in the blood samples. Results have shown that the female animals subjected to CHH had lower levels of AP than the control female rats during all the studied periods whereas the AP of male hypoxic rats was only transiently diminished. All these changes were abolished by castration. PRA was not altered in either sex. The enzymatic complex was higher in male than in female control animals and decreased after castration in both hypoxic and control male rats. Ao was decreased by CHH in both sexes of intact rats and in female castrated animals. The renin substrate was higher in male than in female intact rats and decreased after castration in male animals. ALDO was increased after CHH only in male rats. Control female rats have higher levels of ALDO than male animals. Changes in the renin-angiotensin-aldosterone system related to CHH and also significant differences between sexes suggest that adrenal and gonadal corticosteroids may be involved in the main alterations presently observed.

Aldosterone↗
PubMed1986

Ranitidine and somatostatin. Their effects on bleeding from the upper gastrointestinal tract.

In a randomized, double-blind placebo-controlled clinical trial, the effect of ranitidine was compared with the effect of somatostatin in the control of massive gastrointestinal tract bleeding. Ninety-six patients completed the study. Rates of continuing bleeding and death, incidence of surgery, and blood transfusion requirements were not significantly different in the three treatment groups. Eighteen of the 96 patients presented with a visible vessel at endoscopy. In this group the percent of patients with continuing bleeding, mean transfusion requirements, and mortality were significantly higher than in patients without a visible vessel. Seven patients with a visible vessel underwent surgery and six survived; 11 patients underwent conservative measures and eight died. Ranitidine and somatostatin do not seem to alter the clinical course of patients with upper gastrointestinal tract hemorrhage.

Adult↗
PubMed1986

Vascular renin-like activity in aorta and mesenteric artery of the rat.

Vascular renin-like enzymatic activity (VRLA) has been measured in the artery wall of control and experimental rats. The following groups have been studied: 1-normal salt diet; 2-high salt diet; 3-low salt diet; 4-bilateral nephrectomy (Nx); 5-sham operated for Nx. VRLA was evaluated in the aorta (ARLA) and in the mesenteric arteries (MRLA). Blood samples were obtained for plasma renin activity (PRA) determination. High salt diet decreased PRA, ARLA and MRLA whereas low salt diet increased PRA, did not change ARLA and decreased MRLA. PRA was almost undetectable in Nx animals while ARLA showed a 40% reduction and MRLA was unchanged in these animals. These results would indicate that the changes in PRA induced different variations in the renin-like content of the aorta and the mesenteric artery. The differences could be mainly due to two factors: 1) the capacity of the vascular tissue to bind circulating renin and 2) the capacity of each tissue to synthetize renin-like material in situ.

Animals↗
PubMed1985

Effect of caerulein in patients with biliary colic pain.

A randomized placebo-controlled double-blind trial was carried out in 24 patients with biliary colic pain in order to evaluate the analgesic effect of caerulein (CRL). Caerulein (1 ng/kg . min infused intravenously over 15 min) showed an analgesic effect that was significantly higher than placebo (p less than 0.001). The analgesic action of CRL was not inhibited by naloxone (0.4 mg intravenously, administered two times). Further, the effect of i.v. CRL or saline on artificially induced biliary tree hypertension was studied in 7 patients with a T-tube common bile duct drainage. During saline intravenous administration, increasing biliary tree pressure resulted in pain in 5 patients, with the threshold for pain being 40 cmH2O. During CRL intravenous infusion, significantly higher perfusion pressures were required to achieve a given common bile duct pressure and the pressure threshold for pain was not reached. Consequently, pain was prevented in all patients. These data suggest that CRL relieves biliary colic pain by reducing biliary tract pressure.

Adult↗
PubMed1985

Intrathecal dermorphine in postoperative analgesia.

The effectiveness of intrathecal morphine (500 micrograms), intrathecal dermorphine (20 micrograms) and routine intramuscular pentazocine (30 mg) in the relief of postoperative pain, was compared in 150 consecutive patients after elective surgery, in a prospective randomized double blind study. The analgesic effect of intrathecal dermorphine was found to be profound and to last significantly longer (43.41 +/- 1.64 hr) than intrathecal morphine (34.45 +/- 2.35 hr) or the routine pentazocine therapy (10.79 +/- 2.23 hr). The mean postoperative hospital stay in the intrathecal dermorphine (5.6 +/- 4) and morphine groups (6.3 +/- 45) was significantly shorter than in the control group (8.7 +/- 42). Side-effects, as urinary retention, vomiting and headache, were not significantly different in the three groups of patients.

Adult↗
PubMed1985

The brain renin-angiotensin system and the development of DOC-salt hypertension.

UNLABELLED: The effect of captopril, given in the drinking fluid, on the development of DOC-salt hypertension was analyzed. Although captopril did not prevent an increase in blood pressure (BP) elicited by DOC-salt, captopril did diminish BP in both DOC-salt and control animals. From the first week of treatment DOC-salt rats increased their fluid intake (FI). At the end of the experiment, captopril reduced this increment (655% to 357%). At the same time plasma angiotensinogen was diminished (-35%; p less than 0.001) and cerebrospinal fluid (CSF) substrate concentration increased (+33%; p less than 0.02) in DOC-salt rats, captopril did not modify these changes. In control rats captopril did not alter FI, depleted plasma angiotensinogen, (-73%; p less than 0.001), did not change the central prohormone and increased plasma renin activity (PRA) (+260%; p less than 0.001). IN CONCLUSION: CSF angiotensinogen concentration changes as previously found in CNS while a clear dissociation between plasma and CSF angiotensinogen was found in DOC-salt rats. In these animals the hypertension was not clearly affected by captopril treatment. However the effect of the converting enzyme inhibitor suggests that the central renin-angiotensin system could participate in the increase in FI.

Angiotensinogen↗
PubMed1985

Renin-like activity in vascular tissue of DOC-salt hypertensive rats.

The presence of isorenin active at the physiological pH was investigated in DOC-salt hypertensive rats. The effect of chronic captopril treatment was analyzed in similarly treated animals and in control rats. The levels of the plasma (PRA) and vascular enzyme (VRLA) were compared with those of untreated control animals. DOC-salt administration was maintained during 4 or 8 weeks. Captopril was given in the drinking fluid beginning 4 days before DOC-salt treatment. Renin-like activity was measured in the aorta and mesenteric arteries. DOC-salt treatment reduced PRA to almost undetectable levels while aorta renin-like enzyme only decreased to 50% at 4 weeks and was not changed at 8 weeks. Isorenin levels in the mesenteric artery did not show any significant variation. Captopril did not prevent the increase in blood pressure due to DOC-salt administration and it induced a significant increase in PRA and in VRLA in control rats whereas it did not increase either - enzyme in DOC-salt treated rats. In summary these results confirm the existence of a vascular isorenin and suggest that both binding and local synthesis of the enzyme could take place in the arterial wall.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1985

Nutritional effects of total gastrectomy. A prospective randomized study of Roux-en-Y vs Longmire-Mouchet reconstruction.

A prospective randomized study was carried out to evaluate the nutritional and clinical results of two reconstructive procedures after total gastrectomy for gastric cancer: Longmire-Mouchet (LM) operation with loop interposition and maintained duodenal transit and Roux-en-Y (RY) reconstruction with duodenal exclusion. 22 patients, 11 with LM reconstruction and 11 with RY reconstruction were studied pre-and postoperatively. The average follow-up was of 30 +/- 8 months. The clinical results were shown to be substantially similar to the two groups. No patients complained of heartburn or dysphagia. At esophagoscopy no signs of esophagitis were detected in both groups. The two time course curves of body weight variation did not show statistically significant differences even though in RY patients the body weight has reverted more rapidly to basal values.

Aged↗
PubMed1984

Prostaglandins in commercial milk preparations. Their effect in the prevention of stress-induced gastric ulcer.

To determine if prostaglandins might be the gastroduodenal mucosal protective components in milk, concentrations of prostaglandin E2 (PGE2), thromboxane B2, and 6-keto-PGF1 alpha (the major metabolite of prostacyclin) were measured in aliquots of commercial milk. Whole milk, heavy cream, and yogurt each contained more than 3 ng/mL of PGE2, whereas low-fat milk (2.04 +/- 0.18 ng/mL) and milk from three nursing mothers (0.66 +/- 0.05 ng/mL) contained substantially less. Levels of thromboxane and prostacyclin were much lower, in general, less than 500 pg/mL. In a cold-restraint stress ulcer model in rats, milk was able to inhibit the development of gastric ulcers (50% and ulcer index 5.0 +/- 2.1 v control, 90% and 18.9 +/- 3.8, respectively). Charcoal treatment, which depleted more than 95% of the prostaglandins, rendered the milk nonprotective (80% and ulcer index 15.0 +/- 1.4). These observations are consistent with the concept that prostaglandins may be responsible for the presumed beneficial effects of milk in the prevention and treatment of peptic ulcer disease.

Animals↗
PubMed1984

Neonatal 6-hydroxydopamine treatment and the development of renal hypertension in the rat.

The onset and development of 2 kidney-2 clip renal hypertension was studied in chronically sympathectomized rats treated with 6-hydroxydopamine (6-OHDA) immediately after birth and with adrenal demedullation performed at the time of clipping. Blood pressure (BP) was lower in 6-OHDA treated animals than in untreated controls and the rate of hypertension development was similar in both groups. Urinary excretion of norepinephrine (NE) was significantly decreased during the 15th week and normal by the end of the 20th week. The cardiac NE content reached negligible levels while the mesenteric arteries retained 50% of its content. In the central nervous system (CNS) the 6-OHDA treatment induced a significant increase in NE concentration in the brain stem and medulla oblongata and a significant decrease in cerebellum. Hypertension produced a significant decrease in NE content in the brain stem while 6-OHDA treatment in hypertensive rats resulted in a generalized NE depletion in all the CNS areas. Results have shown that 6-OHDA treatment does not produce a complete and generally distributed sympathectomy; treatment reduces the level of BP but does not change the slope in BP increase.

Animals↗
PubMed1984

Norepinephrine turnover in the heart and blood vessels of rats subjected to bilateral renal infarction.

The total norepinephrine (NE) content, the uptake of [3H]NE, the turnover rate and the synthesis rate of the neurotransmitter at the heart and blood vessels have been studied during the development of hypertension in rats subjected to bilateral renal infarction. Normal and sham-operated rats were used as controls. Fifty percent of the rats with renal infarction became hypertensive. The weight of the hearts and blood vessels of the experimental animals was significantly increased 15 days after renal infarction. Changes were greater in hypertensive animals. NE concentration in the heart was slightly decreased without achieving statistical significance, while total NE content was unchanged. In the artery wall NE concentration was significantly decreased in normotensive and hypertensive operated rats. [3H]NE uptake in the heart and blood vessels was similar in experimental and control animals. In relation to NE turnover, in both the heart and blood vessels, normal and sham-operated animals behaved as one population while normotensive and hypertensive rats behaved as another population. The rate constant of NE turnover was increased in both tissues of operated experimental animals without achieving statistical significance in the case of the heart. NE synthesis rate was unchanged in the cardiac muscle but was significantly increased in the blood vessels of operated animals. Present data indicate that results describing NE dynamics in the heart cannot be extrapolated for the blood vessels level; on the other hand changes in the neurotransmitter do not seem to be related to the development of high blood pressure after renal infarction in the rat.

Animals↗
PubMed1983

Vascular structural changes in the artery wall of unilateral nephrectomized rats.

Wet and dry weight, concentration and total amount of nucleic acids and proteins, and incorporation of tritiated thymidine were measured in the arteries of rats after 7 and 15 days of unilateral nephrectomy, sham operation and in control animals. Arteries of uninephrectomized rats showed increased wet and dry weight, increased DNA and protein content after 7 and 15 days and a higher rate of tritiated thymidine uptake after the first week. These results suggest an early proliferative process in the arteries of unilateral nephrectomized rats.

Animals↗
PubMed1983

Prostaglandin generation in the gastric mucosa of rats with stress ulcer.

Prostaglandins, normally synthesized by the gastric mucosa, have been shown to prevent the formation of experimentally induced ulcers, including stress ulcers. A physiologic role of these compounds in the protection of the gastric mucosa has been postulated. In order to assess the role of endogenous prostaglandins in the pathogenesis of stress ulceration, we measured the amounts of prostaglandin E (PGE) generated by gastric mucosal samples from rats exposed to cold restraint stress. Stress induced a significant inhibition of PGE biosynthesis by the gastric mucosa. The inhibition was similar to that caused by indomethacin. The degree of inhibition of PGE generation significantly correlated with the severity of the gastric mucosal lesions (P less than 0.001). Identical effects were identified in antrum and fundus. The decrease of PGE mucosal biosynthesis seems to be a major determinant in the pathogenesis of stress ulceration.

Animals↗