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Biomedical subjects

A Jost

Publications and source records attributed to A Jost.

At least 109 records · Page 6Linked to original sources
PubMed1966

Norepinephrine methylation in fetal rat adrenals.

The activity of phenylethanolamine-N-methyl transferase, the enzyme that methylates norepinephrine to form epinephrine, increases rapidly in the fetal rat adrenal during the day preceding epinephrine accumulation. The developmental increase in enzyme activity and the accumulation of epinephrine are prevented by fetal hypophysectomy (decapitation). Administration of adrenocorticotrophic hormone or cortisol acetate largely reverses the effect of fetal decapitation.

Adrenal Glands↗
PubMedDate not supplied

Basic sexual trends in the development of vertebrates.

The chain of events occurring during sexual development involves successive steps: genetic sex, gonadal sex and body sex. The latter comprises the genital tract, secondary sex characters and neural structures mediating sexual interest and appetite. Body sex obeys a hormonal control. In the absence of any hormone it develops in conformity with the homozygous sex type--feminine in mammals, masculine in birds, newts and one lizard studied so far. Similar differences have been observed for sex behaviour in some mammals and birds. It has been suggested that the sex of the gonads is determined by the presence (or absence) of the histocompatibility antigen produced by the sex chromosome of the heterozygous sex (Y or W). However, in newt or Xenopus graft chimaeras as well as in bovine freemartins, testicular dominance over presumptive ovaries is obvious whatever the mode of chromosomal control of sex. A unifying concept for sex differentiation in all vertebrates, accounting for the long series of recognized data, is still difficult to delineate.

Animals↗