Showing papers by "Bruce S. McEwen published in 1973"
146 citations
TL;DR: Thesein vitro results agree with the regional distribution of binding obtained in previousin vivo labeling experiments, and it is suggested that, in binding to the cytosol protein, progesterone prevents nuclear accumulation of [3H]corticosterone, and the likelihood of cytOSol to nuclear transfer of hormone is discussed.
118 citations
TL;DR: Levels of 5HT in the female brain were significantly higher than those in the male on postnatal days 10, 12, and 14, though not on days 2, 4, and 8 or on days 16 and 25.
Abstract: Transient sex differences of 5-hydroxytryptamine (5HT, serotonin) concentrations were found in the combined forebrain and midbrain of the neonatal rat. 1) Levels of 5HT in the female brain were significantly higher than those in the male on postnatal days 10, 12, and 14, though not on days 2, 4, and 8 or on days 16 and 25. 2) Castration of males on day 1 resulted in a nonsignificant elevation of brain 5HT on day 12 compared to intact males. 3) Ovariectomy of females on day 1 resulted in a significant reduction of brain 5HT on day 12 compared to intact females. 4) Injection of androgens in females on day 1 resulted in reduced brain 5HT measured on day 12 and day 14. 5) Injections of estrogens on day 1 elevated brain 5HT measured on days 8, 12, and 14 in females, and measured on days 8 and 12 in males. 6) When administered on day 11, these hormones had other effects: estrogen did not increase male brain serotonin measured on day 14, but did increase 5HT levels in the female brain; testosterone did not lower...
90 citations
Journal Article•
63 citations
TL;DR: In the earliest stages of regeneration the proportion of transported RNA to TCA‐soluble material was considerably higher than normal, suggesting that the regenerating fibres arrived in the tectum already carrying RNA.
Abstract: After injection of the tritiated RNA precursors [3H]guanosine, [3H]uridine or [3H]orotic acid into the eye of goldfish, labelled TCA-soluble material and RNA appeared to be axonally transported to the contralateral optic tectum. From the time courses of arrival in the tectum,‘average’rates of transport of 6 mm/day for the soluble material and 1·7 mm/day for the RNA were calculated. If the optic nerve was cut after the transported material had arrived in the tectum, about 60 per cent of the TCA-soluble material disappeared by 7 days after the cut, but almost none of the RNA. After a further 8- to 13-day period, the TCA-soluble material had declined by a further 50 per cent from the 7-day value, but the RNA by only 20 per cent. Thus, relatively little RNA was lost when the optic axons degenerated, an observation which suggested that the RNA might be extra-axonal. However, if the optic nerve was crushed before the arrival of the transported material, RNA did not appear in the tectum until the regenerating optic nerve fibres arrived. Therefore, the presence of RNA must be dependent on intact nerve fibres. Moreover, in the earliest stages of regeneration the proportion of transported RNA to TCA-soluble material was considerably higher than normal, suggesting that the regenerating fibres arrived in the tectum already carrying RNA. This implies that the RNA itself was transported in the optic fibres.
42 citations
TL;DR: The chemistry of glucocorticoid action in brain by following the interaction of the hormone itself with this organ is reviewed, with results serving to direct attention to a particular cellular mechanism of hormone action and to certain brain regions for further neurochemical and physiological studies.
Abstract: Publisher Summary This chapter reviews the chemistry of glucocorticoid action in brain by following the interaction of the hormone itself with this organ. This approach has provided information as to the subcellular and neuroanatomical location within the rat brain of glucocorticoid binding sites-presumptive “receptors”—located in the cell nuclei and soluble portion of the tissue. The results serve to direct attention to a particular cellular mechanism of hormone action and to certain brain regions for further neurochemical and physiological studies. Steroid hormones act directly on the brain to regulate pituitary hormone secretion and influence behavior. Thus, from the point of view of neuroendocrinology and physiological psychology, the brain is a target organ for steroid hormones, but the chemistry of the hormone-brain interaction has only recently come under intensive investigation. The soluble binding protein differs from that in blood and appears able to transfer [ 3 H] corticosterone to isolated cell nuclei in vitro. Nuclear uptake is also demonstrated in brain tissue slices and is shown to be strongly temperature-dependent.
23 citations