Learn More
The effect of continuous stimulation of splanchnic nerves at 1, 3, and 10 Hz on the secretion of catecholamines from the isolated rat adrenal gland was examined. Secretion evoked at 10 Hz declined over 60% in 1 h, and by the end of 4 h the secretion was only 10% of the initial value. The secretion evoked at 3 Hz was unchanged in the first hour, but showed a(More)
Fluorescence imaging of indo-1 loaded cells was used to monitor influx and distribution of Ca2+ in cell bodies, neurites and growth cones of sympathetic neurons cultured from embryonic chick. Similar experiments on release of tritiated noradrenaline were performed to assess the relationship between intracellular Ca2+ concentration ([Ca2+]i) and transmitter(More)
The results of the present experiments demonstrate that embryonic sympathetic neurons initially selected in culture by nerve growth factor could be subsequently supported by raising potassium concentration of the medium to 35 mM. Alternatively, neurons initially selected by 35 mM potassium could be supported in a normal culture medium but supplemented with(More)
A single stimulus applied to sympathetic neurons co-cultured with cardiac cells produced a very small increase in the release of tritiated norepinephrine and intracellular free Ca2+ concentration ([Ca2+]i), but evoked a typical neuronal action potential. Treatment with 10 mM tetraethylammonium caused a dramatic increase in the responses to a single(More)
The functional behavior of embryonic chick sympathetic neurons was determined by inducing release of [3H]norepinephrine by electrical stimulation of sympathetic neurons growing in the chick heart and in culture, with and without heart cells. A very close correspondence between the functional behavior of neurons developing with the heart cells, either in(More)
Tryptic digestion of tyrosine hydroxylase (TH) isolated from rat adrenal glands labeled with 32Pi produced five phosphopeptides. Based on the correspondence of these phosphopeptides with those identified in TH from rat pheochromocytoma cells, four phosphorylation sites (Ser8, Ser19, Ser31, and Ser40) were inferred. Field stimulation of the splanchnic nerves(More)
The functional integrity of adrenal chromaffin storage vesicles was studied in the perfused rat adrenal gland subjected to intense exocytosis. Continuous perfusion with 55 mM K+-Krebs solution produced a large and uninterrupted secretion of catecholamines. Total amounts secreted within 45 min were 4.66 micrograms and represented almost 30% of the total(More)
We studied the effects of lanthanum (La3+) on the release of 3H-norepinephrine (3H-NE), intracellular Ca2+ concentration, and voltage clamped Ca2+ and K+ currents in cultured sympathetic neurons. La3+ (0.1 to 10 microM) produced concentration-dependent inhibition of depolarization induced Ca2+ influx and 3H-NE release. La3+ was more potent and more(More)
The aim of the present study was (1) to evaluate the functional contribution of nicotinic and muscarinic receptors of the rat adrenal medullary cells in the secretion of catecholamines evoked by exogenous and endogenous acetylcholine, (2) to know whether the ratio of epinephrine to norepinephrine in the perfusate of the adrenal gland stimulated with various(More)
1. A method of studying the secretion of catecholamines (CA) in the isolated perfused rat adrenal gland by transmural stimulation or by application of acetylcholine (ACh) has been described. 2. Secretion of CA was practically linear in response to ACh administration, starting from 4.42 microM to 1.32 mM. Transmural stimulation enhanced secretion from a(More)