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M C Muñoz

Publications and source records attributed to M C Muñoz.

52 records · Page 3Linked to original sources
PubMed1984

[Effect of olfactory bulbectomy on plasma levels of glucose, lipids and corticosterone in the rat].

The effect of bilateral olfactory bulbs removal on the peripheral glucose, lipids and corticosterone levels has been studied in Wistar male rats. After 30 days of the olfactory bulbectomy there was found: an increase in the basal values of plasmatic glucose, a significant increase in peripheral levels of the free fatty acids, and a notorius decrease in plasmatic corticosterone at 9 a.m. Other biochemical parameters, such as free glycerol, triglycerides and phospholipids, went unaltered. These after bulbectomy variations, especially the increase in free fatty acids, are discussed in relation to a possible role of the olfactory bulbs on the nutritional, endocrine and nervous factors, which are closely related to the mechanisms involved in the regulation of cellular lypolisis.

Animals↗
PubMed1984

[Effect of cerebral intraventricular administration of 5,6-dihydroxytryptamine and 5,7-dihydroxytryptamine on the cyclic secretion of corticosterone in the rat].

The effect of two potent neurotoxic agents for 5HT neurons, 5,6-DHT and 5,7-DHT, intraventricularly injected, has been studied on the values and rhythm of plasmatic corticosterone secretion in the male Wistar rat model, along an entire day: 4 a.m., 8 a.m., noon, 5 p.m. and midnight. The dose administered for each drug was 100 micrograms/animal in a single injection. The levels of corticosterone were determined 15 and 30 days post-injection. The effects observed for both drugs were similar at similar times: highly significant decreases in all the studied points which fall under the same line of secretion and evince an absolute inhibition of the cyclic rhythm. There are no significant differences among the values obtained with different drugs at various times. The contents of NA and 5HT significantly decrease for both drugs especially those of the 5HT on the 15th day. 30 days after the injection there is a small recovery of 5HT, but differences with control values are still significant. On the other hand the recovery of NA was almost total (near 100%). The results are discussed within the highly controversial frame of the influence of central 5HT neurons on the various types of secretion of the hypothalamic-pituitary-adrenal axis. The data obtained with this "chronic model" are confronted with those from other authors who have used drugs with transitory effect on the 5HT brain metabolism.

5,6-Dihydroxytryptamine↗
PubMed1984

[Effect of various doses of naloxone on circulating corticosterone levels in the rat].

The effect of three different doses of naloxone (2.5, 5 and 10 mg/kg w.i.p.), on the corticosterone levels has been studied in the Wistar male rat model, at 9 a.m. and 5 p.m. The 5 mg/kg w. dose, induces a significant increase on the p.m. values, while the 10 mg/kg w. dose determines highly significant increases on the a.m. and p.m. values, referred to its controls the p.m. ones being percentually higher. The putative role of endogenous opiates, given the naloxone specific antagonism in the activity of the hypothalamic-pituitary-adrenal axes is discussed, while the changes observed after naloxone injection are analyzed to see whether they are provoked by a direct effect of the drug on the adrenal gland or are mediated by a central mechanism.

Animals↗
PubMed1983

[Effect of alpha-methyl-p-tyrosine and dihydroxyphenylalanine on plasma corticosterone levels in rats pretreated with prednisolone acetate].

The effects on hypothalamic-pituitary-adrenal function and on negative feed-back action of a synthetic adrenal steroid, prednisolone acetate, have been studied in female Wistar rats treated with alpha-methyl-p-tyrosine (alpha MpT) and L-dihydroxyphenylalanine (L-DOPA) administered for six consecutive days. The parameter for study was taken from the plasmatic changes of corticosterone levels. alpha-MpT injection determines an increase of plasmatic corticosterone values, while L-DOPA injection produces the opposite effect, decreasing corticosterone levels as compared to the saline control group. The simultaneous administration of prednisolone acetate 250 micrograms/kg weight s.c. for six consecutive days to alpha-MpT or L-DOPA determines the following effects: a) With alpha-MpT the negative feed-back action of prednisolone was not modified. b) With L-DOPA this action of the steroid is cancelled and the plasmatic corticosterone values are increased significantly. These changes have been related to modifications of the catecholamines content in the brain. The importance of the catecholamines on the activity of the hypothalamic-pituitary-adrenal axis is discussed under experimental condition, specially the effects of L-DOPA, which depends for its activity on the presence or absence of prednisolone.

Adrenal Cortex↗
PubMed1983

[Malignant histiocytosis in children].

Three cases of malignant hystiocytosis in infants are reported. Two of them are medullary hystiocytic reticulosis and the other one familial erytrophagocytic lymphohystiocytosis. Clinical and pathological differences and similarities between both entities are discussed. Our experience sustains the hypothesis that RHM and LEF are two forms of a same disease.

Age Factors↗
PubMed1982

[Influence of the habenular complex on the cyclic secretion of plasma corticosterone in rats].

The effect of bilateral lesion of the medial and lateral habenular nuclei on the corticosterone plasmatic levels determined at 8 a.m. and 5 p.m. was studied in adult female rats 30, 60 and 90 days after the lesion. 30 days after the lesion a drop in plasmatic values and the suppression of the normal diurnal fluctuation in corticosterone plasmatic levels were found. At 60th day these changes still persist. At 90th day, the corticosterone levels and its daily fluctuations reversed to normal values. These data suggest that the habenular complex is a nervous area participant in the activity modulation of the hypothalamus pituitary-adrenal system. The possible role of the habenular nuclear complex in the maintenance of the rhythm is discussed taking into account its afferent and efferent connections, especially with the olfactory system and the limbic ventral tegmental area, whose direct involvement in this rhythm has been shown.

Adrenal Cortex↗
PubMed1979

Use and acceptance of the "Paper Pill" among an urban clinic population.

A randomized, crossover study comparing the acceptability of two presentations of the same oral contraceptive, a paper formulation and the conventional tablet, was carried out among two-hundred-and-seventy women attending two urban family planning clinics in Mexico City. During the first three cycles of use, the percentage of women discontinuing the medication for side effects was almost identical in the two groups. Although the paper formulation failed to demonstrate any major advantage in terms of continuation or acceptability, it was preferred by a majority of the women who began oral contraception with its use.

Adolescent↗
PubMedDate not supplied

[Effect of cyclosporin A, azathioprine, and methylprednisolone on plasma levels and heart atrial content of atrial natriuretic peptide in the rat].

In Wistar normotense male rats of six months old the effect of Cyclosporine A (Cys A), azathioprine (AZA) and methyl prednisolone (M-Pred), alone or associated, on the plasmatic levels and atrial content of the atrial natriuretic peptide (PNA) have been studied. The values of creatinine, urea, sodium a potassium were also measured in serum. This treatment was maintained for 30 consecutive days at these doses: Cys A (5.00 mg/kg b.w./day), AZA (2.50 mg/kg b.w/day) and M-Pred (20.00 mg/kg b.w./day), being the peritoneal the way of administration. Eight groups were organized: control, vehicle, Cys A, AZA, M-Pred, Cys A + M-Pred, AZA + M-Pred, Cys A + AZA + M-Pred. All the above parameters were estimated at 24 hours after respective injections. No changes are found after Cys A or AZA in the plasmatic and atria contents of PNA. Nevertheless, m-Pred alone or in association determines high increases of PNA in plasma and tissue. The other parameters are unchanged. The data reveal the beneficial use of M-Pred, glucocorticoid of the low mineral activity, in the therapy of rejection in cardiac transplantation. On the other hand, Cys A and AZA appear not to be important in the secretion and atrial synthesis of PNA.

Animals↗