The effect ofβ-adrenergic stimulation and blockade on the efflux of PGE1-like material from the isolated perfused rabbit heart

Summary Prostaglandin (PG) release was measured from the isolated perfused rabbit heart. The effects of -adrenergic stimulation and blockade suggest that PG synthesis is regulated in part by adrenergic mechanisms.     

Effects of ACTH and diabetes on phospholipid metabolism in adrenal mitochondria.

Incorporation of 32P into adrenal mitochondrial phospholipids (PL) incrased in ACTH-treated rats, but it decreased in diabetics, inspite of the fact that these animals showed adrenal overacity. Since diabetics did not show increased 11 beta-hydroxylation. as opposed to ACTH-treated rats, it is suggested that the stimulation of this enzyme activity by exogenous ACTH is related to an increased turnover of PL at the mitochondrial membrane. The process is impaired in diabetics and prevents the stimulation of 11 beta-hydroxylation.     

A centrally induced vasodepressor response after intravenous administration of whole venom ofNaja mossambica pallida in cats

Summary Naja mossambica pallida venom administered i.v. (300 /kg) produces an initial brief fall in blood pressure, due to a direct myocardial depressant effect, and a sustained fall due to central depressant effect.This study was supported by University of Nairobi research grants (670–376). We also thank Mr E. Njogu for photographic assistance.     

Metabolism of the snailCryptozona ligulata during regeneration of optic tentacles

Summary The biochemical changes in the hemolymph and tissues were followed during regeneration of the optic tentacles of the snailCryptozona ligulata (Pulmonata-Stylommatophora). There is a remarkable increase in total carbohydrates in hemolymph and tissues and glycogen in tissues at the expense of free amino acids and fatty acids. It is clear that ablation of the optic tentacles stimulates carbohydrate synthesis through glyconeogenic routes. The optic tentacles regenerate completely in 18–21 days.     

High-performance reversed-phase liquid chromatography (HPLC) of favism-inducing factors inVicia faba L.

Summary A HPLC assay for L-Dopa, convicine, and vicine in broad-bean extracts has been developed. The distribution of these compounds in the different organs of the plant has been studied, especially in the seeds, where their presence may cause favism if the beans are used as food.Work supported by C.N.R. through Progetto Finalizzato Miglioramento delle produzioni vegetali per fini alimentari ed industriali mediante interventi genetici. Sottogrogetto leguminose da granella. Paper No. 200.     

Structure specificity of some immunoadjuvant synthetic glycopeptides

Summary The immunoadjuvant activity of muramyl dipeptide seems to be critically dependent on the type of substitution of the -carboxyl group of the D-isoglutamine residue. Moreover the nonapeptide L-Ala-D-isoGlu-L-Lys-D-Ala-(Gly)₅-OME also shows a definite effect.     

Effect of X-537A on the phosphorylated protein in sarcoplasmic reticulum vesicles

Summary The effect of the antibiotic X-537A on the phosphorylated ATPase (EP) was investigated. The results show that X-537A depresses the level of EP which is dependent on the Ca²⁺ gradient, while the Ca²⁺-independent EP is not affected. Acknowledgments. This work was supported by grants from the Instituto de Alta Cultura of the Portuguese Ministry of Education (No. CB/2) and the Calouste Gulbenkian Foundation.