PubMed Health⌕ Search

Biomedical subjects

N Basso

Publications and source records attributed to N Basso.

At least 37 records · Page 2Linked to original sources
PubMed1987

Chronic administration of ketanserin and the development of two-kidney-two-clip Goldblatt renovascular hypertension in the rat.

The effect of ketanserin (Kt) has been analyzed during the development of two-kidney-two-clip (2k-2c) renovascular hypertension in the rat. Male Wistar rats were divided into four experimental groups: (1) clip Kt (ClKt) (n = 12)--A silver clip (0.25 mm width) was placed in each renal artery 3 days after beginning the administration of Kt (10 mg/kg/day) in the drinking water; (2) sham Kt (ShKt) (n = 13)--Similar to group 1, but the clips were placed in, and immediately removed from, the renal arteries; (3) untreated clip (UCl) (n = 10)--Similar to group 1, but the rats drank water; (4) untreated sham (USh) (n = 10)--Similar to group 2, but the rats drank water. Blood pressure (BP) was measured before surgery and was followed weekly for 7 weeks. At the end of this period, blood and cerebrospinal fluid (CSF) samples were obtained in all the animals. Plasma renin activity (PRA) and plasma and CSF angiotensinogen concentration (AoC) were evaluated. The results have shown that Kt partially inhibited the increase in BP induced by bilateral renal ischemia (BP: UCl rats 180.5 +/- 12.4 versus ClKt rats 149.8 +/- 5.1 mm Hg; p less than 0.01; USh rats 116.7 +/- 3.7; ShKt rats 114.4 +/- 5.0 mm Hg). PRA was similar in hypertensive and control rats whether or not they had received Kt. AoC in plasma was decreased in clipped treated and untreated rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensinogen↗
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

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↗
PubMed1977

Acid and gastrin levels after bombesin and calcium infusion in patients with incomplete antrectomy.

In 17 patients with postoperative recurrent peptic ulcer, incomplete antrectomy (I.A.) was found by endoscopic biopsies in 5. No evidcence of I.A. was found in the remaining 12 patients. Gastric acid output and gastrin levels were measured in basal conditions and following a calcium I.V. infusion (4 mg/kg hr of Ca++ over 4 hr) and a bombesin (BBS) I.V. infusion (15 ng/kg min over 90 min). Basal gastrin levels were significantly differnt in the two groups of patients: BBS infusion augmented significantly serum gastrin levels in all patients with I.S., while BBS infusion had no significant effect on serum gastrin levels in the group of patients without I.A. Acid output following BBS infusion showed a pattern similar to the pattern seen for gastrin. Calcium infusion augmented gastric acid secretion and gastrin levels in the patients with I.A.; however, the response to calcium could not clearly separate in all instances patients with I.A. from patients without I.A. It is concluded that the "BBS infusion test" may be heplful in the diagnosis of I.A. in patients with postoperative peptic ulcer.

Adult↗
PubMed1977

Progress in the treatment of acute gastroduodenal mucosal lesions (AGML).

This article presents an analysis of acute gastroduodenal mucosal lesions (AGML) based on a review of current literature and the personal experience of the authors. The pathology of AGML involes two distinct types of lesions, namely, superficial erosions confined to the acid-secreting gastric mucosa and presenting as erosive hemorrhagic gastritis, and acute ulcers that occur in the alkaline gastric mucosa and duodenum. The etiology of these two lesions is very likely different. Acut gastroduodenal ulcers, best known as stress ulcers, are probably "peptic" lesions, whereas erosive hemorrhagic gastritis appears to be due to pathologic back diffusion of hydrogen ions caused by a breakdown of the gastric mucosal barrier as a result of endogenous factors, such as gastric mucosal ischemia, and sometimes exogenous factors, such as alcohol, urea, and acetylsalicylic acid. Catecholamine hypersecretion resulting from severe stress, such as occurs in hypovolemia, sepsis, and hypercapnea, contributes to ischemia of the gastric mucosa by producing splanchnic vasoconstriction. The key to the diagnosis of AGML is early endoscopy in all cases of upper gastrointestinal bleeding. Therapy for AGML should begin with a trial of medical measures directed at restoring effective perfusion of tissues and removing hydrogen ions from the stomach by gastric washing. Medical therapy is effective in 80% of patients with erosive hemorrhagic gastritis, but surgical treatment is usually required in acute gastroduodenal ulcer. When surgery is necessary for either type of lesion, vagotomy with hemigastrectomy appears to be the most effective operation. The personal experience of the authors has involved 36 patients with AGML who were treated in three periods between 1968 and 1976. The mortality rate of patients with AGML has been reduced from 50% in the first 2 years to zero in the last 2 years by the use of emergency endoscopy for diagnosis, appropriate medical therapy, properly timed and executed surgery, and, most recently, selective angiography.

Acute Disease↗
PubMed1977

Retained antral mucosa in pancreaticoduodenectomy patients.

Thirteen patients with pancreaticoduodenectomy were studied. In three patients presenting with stomal ulcer or bleeding stomitis, endoscopic biopsies showed the presence of retained antral mucosa (RAM). No disease and no RAM was present in the remaining ten patients. Bombesin (BBS) infusion augmented both gastric acid and gastrin secretion in the group with RAM, whereas no change was apparent in the remaining ten patients. The BBS infusion test is useful in detecting stomal ulcer high risk pancreaticoduodenectomy patients.

Adult↗
PubMed1977

Vascular renin-like activity and blood pressure.

Plasma renin activity, reninlike activity present at the artery wall, pressor response to exogenous hog renin, renin half-life time, and renin-like activity present at the artery wall 1 hour after injection of renin were measured in conscious rats 1 month after inducing hypertension by renal artery constriction and contralateral nephrectomy (one-kidney hypertension). Plasma renin activity was higher but without statistical significance in one-kidney hypertensive rats when compared with normotensive or sham-operated animals. Renin-like activity present at the artery wall was significantly increased in hypertensive animals only when compared with one-kidney normotensive rats. Pressor responses to renin in one-kidney hypertensive and normotensive rats were of significantly longer duration than in sham-operated animals. The inactivation rate of exogenous renin followed a first-order reaction with a half-life of 6 minutes in sham-operated rats and of 12 minutes in one-kidney hypertensive and normotensive animals. Decreased inactivation of circulating renin could explain the protraction of the pressor response; however, the slope of the regression equation describing the inactivation of renin in all of the rats was steeper than the slope of the pressor response, indicating a dissociation between blood pressure and plasma renin activity. The renin-like activity present at the artery wall 1 hour after injection of renin was determined in the three groups; the arterial tissue of one-kidney hypertensive rats bound more circulating renin than that of normotensive rats and the latter more than that of sham-operated animals, suggesting the participation of this binding capacity in the protraction of the pressor response and in the maintenance of hypertension.

Animals↗