Search PubMed⌕ Search

Biomedical subjects

E Romero

Publications and source records attributed to E Romero.

At least 127 records · Page 7Linked to original sources

Presence of serotonin in the rat vas deferens: its influence on contractile responses.

Serotonin has been detected in the rat vas deferens. Increase in the serotonin concentration by exposure of the rat vas deferens to L-tryptophan occurs in vitro. p-chlorophenylalanine partly blocks the increase in serotonin concentration induced by tryptophan in vitro but not in vivo. Chronic sympathetic denervation induces an increase in 5-HT concentration. Responses of the vas deferens to transmural stimulation are depressed by pretreatment of rats with p-chlorophenylalanine, and the depression is reversed by incubation in vitro with 5-hydroxytryptophan or serotonin. Serotonin can enhance the response to transmural stimulation at low concentrations but has no effect at higher concentrations. Physostigmine-induced enhancement of the response to stimulation is depressed only by higher concentrations of serotonin. The results raise the question whether endogenous serotonin can act as a modulator of neurotransmission in the rat vas deferens.

Animals↗

Relationships between curing of the F episome by rifampin and by acridine orange in Escherichia coli.

Subinhibitory doses of rifampin cured F(+)Escherichia coli cells from the episome. The target of the drug was transcription because E. coli mutants with a ribonucleic acid polymerase resistant to rifampin were not cured. The experimental conditions required for optimal curing with rifampin very closely resembled those required for curing with acridine orange. Mutants were found which are more resistant to curing by both acridine orange and rifampin. Probably the two drugs affect a common metabolic step, or alternatively they may inhibit the synthesis of a factor which is necessary for the replication of the episome.

Acridines↗