Biomedical subjects

J J Calvo

Publications and source records attributed to J J Calvo.

41 records · Page 3Linked to original sources

PubMed1982

[Correlation between plasma ferritin and iron from liver and spleen in chicken (author's transl)].

Plasmatic, hepatic and splenic ferritin concentrations, measured by a radioimmunoassay method, have been studied in three groups of animals, with different iron status: In overload, in deficiency and control. Significant differences in plasmatic, hepatic and splenic ferritin concentrations were observed between overloaded and deficient animals. Simultaneously, liver and spleen ferritin iron values, significantly higher in overloaded than in deficient, were also found.

Animals↗

PubMed1981

[Radioimmunoassay of plasma ferritin of Gallus domesticus L].

A new experimental procedure for chicken plasma ferritin based on the method of Luxton et al. has been carried out. All biologic reagents used were obtained in our laboratory: Ferritin from chicken liver, antiferritin antiserum from rabbits and anti-rabbit IgG from goat. Chloramine T procedure was applied to label ferritin with 125I. The iodinated protein was removed from free iodide by use of three chromatographic columns of Sephadex G-25, Sephadex G-200 and Sepharose 6B. Separation of the first antigen-antibody complex was carried out by the double antibody method. The assay working range covers from 21.8 up to 175 ng/ml. As ferritin concentration is higher in chicken plasma than in human, various plasma dilutions ranging from 1/16 to 1/64 were used.

Animals↗

PubMedDate not supplied

Response of exocrine pancreatic secretion to CCK in adrenalectomized rats.

A study was made of the effect of adrenalectomy over different periods of time (6, 15 and 21 days) on exocrine pancreatic secretion in the rat in basal conditions and under stimulation with CCK. It was observed that adrenalectomy does not alter the rate of pancreatic flow but the response capacity to CCK is depressed. The secretion of total protein and amylase decreases significantly after sixth day, reaching the lowest levels after 21 days. Despite this, after 6 days the adrenalectomized rats showed the same capacity of response to CCK as the non-adrenalectomized animals, while after longer periods of time (15 and 21 days) the response to CCK was inhibited. The fact that the lack of glucocorticoids prevents the maturation of zymogen granules seems to be the main reason why the acinar cells do not increase protein secretion in response to CCK at 15 and 21 days after adrenalectomy. It is concluded that the sensitivity of exocrine pancreas to CCK and the amount of zymogen granules in the acinar cells decrease as a function of the time over which the animals are deprived of glucocorticoids.

Adrenalectomy↗

PubMedDate not supplied

Effect of secretin on pancreatic juice proteins in caerulein-induced acute pancreatitis in the rat.

Nine hours after the start of treatment with caerulein in rats, an increase in the weight of the pancreas and an increase in serum amylase levels were observed. Likewise, a significant increase in endogenous secretin occurred in rats with acute pancreatitis. A dramatic reduction in the secretion of total protein and amylase was also observed. A partial recovery of this latter effect was achieved after an infusion of high doses of secretin. Under our experimental conditions, the volume of secretion did not vary in caerulein-treated rats wtih respect to controls, either in resting conditions or under secretin stimulation, which indicates that the ductular cells were not significantly affected. Isoelectrofocusing (IEF) and crossed-immunoelectrophoresis (CIE) studies revealed important alterations in the proteins of the pancreatic juice of rats with caerulein-induced acute pancreatitis. Trypsinogen appeared to be particularly affected, showing an increase in the T2 acidic form with an IEP of 4.4 and a decrease in the basic form T3 with an IEP of 8.0, which splits in other forms with a clear antigenic community. A hydrolase was also observed with an IEP of 6.2. In this sense, secretin administration may also be said to induce a significant improvement in established acute pancreatitis, since it tended to normalize the structure and proportion of the proteins secreted.

Acute Disease↗

PubMedDate not supplied

Dose-response effect of intraduodenal HCl on exocrine pancreatic secretion, portal secretin, and VIP plasma levels in anesthetized rats.

In anaesthetized rats, a dose-dependent effect of different intraduodenal HCl loads (0.6, 1.2, 6 and 12 mmol/h) on exocrine pancreatic secretion and plasma levels of secretin and VIP has been observed. The flow rate of pancreatic juice showed a significant increase at all the doses used; the integrated percentage response (IPR) of flow were 359%, 595%, 894% and 1371% for, respectively, 0.6, 1.2, 6 and 12 mmol/h. The increase of protein output only achieved statistical significance at HCl loads of 6 mmol/h or more; the IPR of protein output were 153%, 305%, 320% and 420% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl. Portal levels of secretin and VIP were measured by specific radioimmunoassays. Significant increase of secretin concentration was observed at HCl loads of 1.2 mmol/h or more, whilst VIP levels only increased significantly after intraduodenal HCl load of 6 mmol/h or more. The IPR of secretin release were 180%, 203%, 280% and 322% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl and IPR of VIP release were 3%, 20%, 244% and 315% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl. Our results suggest that secretin may play a more prominent role than VIP in stimulating exocrine pancreatic secretion in response to intraduodenal loads of acid in this species.

Anesthetics↗