Growth characteristics of postnatal rat adrenal medulla in culture

Abstract

Explants and enzyme-dispersed cells of adrenal medulla from 10-12 day old rats were studied in culture for up to 3 weeks. Adrenomedullary chromaffin cells, nerve cells and satellite cells were clearly discernible. The nerve cells were few in number and did not show catecholaminespecific fluorescence. Chromaffin cells stored catecholamines, as judged by the Falck and Hillarp method, in varying amounts decreasing with age of the cultures and the distance from the explants. Exocytosis profiles observed with the electron microscope suggested that cultured chromaffin cells also released catecholamines. Moreover, the cells formed processes and frequently migrated into the outgrowth. After 6 days in culture, the great majority of chromaffin cells stored noradrenaline as revealed by electron microscopy with few adrenaline-storing cells being visible. Granular vesicles (approximately 80-240 nm in diameter) with cores of different electron densities were occasionally present in the same cell suggesting the occurrence of mixtures of primary and secondary amines. Apart from "chromaffin" granules, small clear and dense-cored vesicles (approximately 40-60 nm) were found both in the somata and cell processes. Chromaffin cells and their processes were often closely apposed and occasionally formed specialized attachment zones. As a whole, chromaffin cells in culture resembled small granule-containing cells in sympathetic ganglia. 0.5 mM dbcAMP prevented dedifferentiation of chromaffin cells as judged by the lack of processes, the size and amount of "chromaffin" granules and the high number of adrenaline-storing cells present after 6 days in culture. NGF caused a striking increase in the number of axons growing out from explants.

Nerve growth factor-induced fiber outgrowth from isolated rat adrenal chromaffin cells: impairment by glucocorticoids.

“…In confirmation of previous experiments (8,15), the dissociated cells could clearly be identified as chromaffin cells, neurons, or Schwann cells. Chromaffin cells were round after plating and became partially polygonal after 2-3 days in culture.…”

“…However, their specific granular vesicles exclusively exhibited highly electron-dense cores, indicating the presence of a primary amine (16). The cores had a diameter of 35-240 nm, which is less than that described for rat adrenal chromaffin cells at the end of the gestation period (17), but which corresponds to the data given for rat adrenal chromaffin cells grown as explants (8).…”

“…Moreover, autoradiographic studies have shown that intravenously injected 125I-labeled NGF is selectively accumulated in adrenal chromaffin cells as in adrenergic neurons (6). After transplantation experiments of adrenal medullary cells had shown that these cells also possess the ability to form processes (7,8), we investigated whether the particular topographical location of the adrenal medulla-ie., its close proximity to the adrenal cortex and concomitant exposure to high glucocorticoid concentrations -is responsible for the lack of formation of neuronal fibers.…”

Nerve growth factor-induced transformation of immature chromaffin cells in vivo into sympathetic neurons: effect of antiserum to nerve growth factor.

“…Fullydifferentiated (12) showed that chromaffin cells dissociated from the adrenal medulla of infant rats produce fiber outgrowth and exhibit structural, ultrastructural, and biochemical features of sympathetic cells when cultured in a NGF-enriched medium. The property of isolated adrenal medullary cells to occasionally produce neurites even in the absence of NGF had been shown in previous experiments (13,14). The authors attribute the NGF effect to the fact that the dissociated chromaffin cells are not under the influence of glucocorticoids released in the intact gland from adjacent cortical cells.…”

“…Forty pregnant rats (Sprague-Dawley) raised in our animal quarters were divided into two groups: 26 rats were operated on as indicated below on day 17 of pregnancy (determined on the basis of the observation of the vaginal plug) and 14 rats were housed in single cages. Upon delivery, half of the pups of 10 litters were injected with 10 ,ug of NGF per g body weight, half of the pups of 4 litters with the immunoglobulin fraction of a specific antiserum to NGF (AS-NGF), and the remaining pups of the 14 litters with vehicle solution.…”