Evidence for a dihydropyridine‐sensitive and conotoxin‐insensitive release of noradrenaline and uptake of calcium in adrenal chromaffin cells

Owen, P J; Marriott, Deborah; Boarder, Michael R.

doi:10.1111/j.1476-5381.1989.tb11933.x

Cited by 54 publications

(35 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…L-type channels predominate the secretion despite their contribution to the total current in single cell experiments is partial or very small, as in the case of BCCs [73,74]. A dominance of L-type channel-mediated secretion is thus reported in bovine [4,[75][76][77], mouse [78,79], rat [9,10,80,81] and cat chromaffin cells [82,83] more or less independently of whether intact adrenal glands or cultured chromaffin cells are used. The reason for this general finding is that during prolonged depolarization (far from physiological conditions) L-type channels are probably more favored because of their slower time-dependent inactivation and lower steady-state inactivation with respect to the other HVA channels (P/Q, N and R), which inactivate more rapidly and completely during prolonged stimuli.…”

Section: L-type Channels and Fast Exocytosis In Chromaffin Cellsmentioning

confidence: 80%

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

et al. 2007

View full text Add to dashboard Cite

Voltage-gated L-type (Cav1.2 and Cav1.3) channels are widely expressed in cardiovascular tissues and represent the critical drug-target for the treatment of several cardiovascular diseases. The two isoforms are also abundantly expressed in neuronal and neuroendocrine tissues. In the brain, Cav1.2 and Cav1.3 channels control synaptic plasticity, somatic activity, neuronal differentiation and brain aging. In neuroendocrine cells, they are involved in the genesis of action potential generation, bursting activity and hormone secretion.Recent studies have shown that Cav1.2 and Cav1.3 are also expressed in chromaffin cells but their functional role has not yet been identified despite that L-type channels possess interesting characteristics, which confer them an important role in the control of catecholamine secretion during action potentials stimulation. In intact rat adrenal glands L-type channels are responsible for adrenaline and noradrenaline release following splanchnic nerve stimulation or nicotinic receptor activation. L-type channels can be either up-or down-modulated by membrane autoreceptors following distinct second messenger pathways. L-type channels are tightly coupled to BK channels and activate at relatively low-voltages. In this way they contribute to the action potential hyperpolarization and to the pace-maker current controlling action potential firings. L-type channels are shown also to regulate the fast secretion of the immediate readily releasable pool of vesicles with the same Ca 2+ -efficiency of other voltage-gated Ca 2+ channels. In mouse adrenal slices, repeated action potential-like stimulations drive L-type channels to a state of enhanced stimulus-secretion efficiency regulated by ␤-adrenergic receptors.Here we will review all these novel findings and discuss the possible implication for a specific role of L-type channels in the control of chromaffin cells activity.

show abstract

Section: L-type Channels and Fast Exocytosis In Chromaffin Cellsmentioning

confidence: 80%

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

et al. 2007

View full text Add to dashboard Cite

show abstract

“…In analogy to chromaffin cells, the N-channel in PC12 cells is not functional (shown in Fig, 1A). Chromaffin cells contain oCgTx binding sites [29,30] and w-CgTx-sensitive currents 131,321 but neither catecholamine secretion nor increase of [Ca2']i transients were antagonized by w-CgTx [33,34]. Fu~he~ore, synaptota~in, a small synaptic vesicleassociated protein which is involved in mediating transmitter release [35], is absolutely non-essential in the secretion process in PC12 cells [36].…”

Section: The L-type Ca2' Channel Expressed In Pc12 Cellsmentioning

confidence: 99%

Cardiac L‐type Ca²⁺ channel triggers transmitter release in PC 12 cells

Avidor

Schwartz

et al. 1994

FEBS Letters

View full text Add to dashboard Cite

*+ Among the various voltage-sensitive Ca charmels present in PC12 cells are the dihy~op~idine (DHP)-sensitive L-channel, the w-conotoxin (w-CgTx)-sensitive N-channel, and an atypical w-CgTx/DHP-insensitive Ca*+ channel. Depolarization-evoked Ca*' entry and [3H]dopamine release is mediated by L-type Ca*' channels determined by the use of Ca*' channel antagonists, and a single protein of 250 kDa is recognized by L-type-specific antibodies. Screening of a PC12 cDNA library revealed two types of Ca*' channels which were identified by partial sequencing. A pcl2-L clone displayed virtually identical sequence homology to the cardiac L-type channel. The identical sequence homology of the single alternative splicing region confirmed clone pcl2-L as the rbC-I transcript, a cardiac-neuronal al subunit expressed in rat brain. Clone pcl2-N displayed identical sequence homology to rbB-I, a neuronal al subunit of the N-type Ca '+ channel expressed in rat brain; Northern blot analysis identified RNA of a size similar to that previously described for rat brain.

show abstract

“…The latter can also be blocked by v-agatoxin IVA at concentrations above 10 Ž . nM Wheeler et al, 1994 Owen et al, 1989;Rosario et al, 1989 . Indeed, while several groups including ours have consistently emphasized the lack of effect of v-conotoxin GVIA 2q Ž in depolarization-evoked Ca influx this paper and Ballesta et al, 1989;Owen et al, 1989;Rosario et al, .…”

mentioning

confidence: 99%

“…nM Wheeler et al, 1994 Owen et al, 1989;Rosario et al, 1989 . Indeed, while several groups including ours have consistently emphasized the lack of effect of v-conotoxin GVIA 2q Ž in depolarization-evoked Ca influx this paper and Ballesta et al, 1989;Owen et al, 1989;Rosario et al, . 1989;Duarte et al, 1993a , others-using single cell w 2q x Ca measurements-have reported the occurrence of i cell-specific and variable inhibitory effects of the toxin Ž .…”

mentioning

confidence: 99%

Regulation of Ca2+ influx by a protein kinase C activator in chromaffin cells: differential role of P/Q- and L-type Ca2+ channels

Sena

Santos

Boarder

et al. 1999

European Journal of Pharmacology

View full text Add to dashboard Cite

Phorbol esters reduce depolarization-evoked Ca 2q influx in adrenal chromaffin cells, suggesting that voltage-sensitive Ca 2q channels Ž . VSCCs are inhibited by protein kinase C-mediated phosphorylation. We now address the possibility that L-and PrQ-type Ca channel Ž . subtypes might be differentially involved in phorbol ester action. In bovine chromaffin cells, short-term 10 min incubations with phorbol Ž .Žw 2q x . 12-myristate 13-acetate PMA inhibited early high K -evoked rises in cytosolic free Ca concentration Ca and the early i 2q

show abstract

Evidence for a dihydropyridine‐sensitive and conotoxin‐insensitive release of noradrenaline and uptake of calcium in adrenal chromaffin cells

Abstract: These results show that in these neurone-like cells, release may be effected by calcium influx through DHP-sensitive but co-conotoxin-insensitive VSCC, a result inconsistent with the suggestion that w-conotoxin blocks both L-type and N-type neuronal calcium channels.

Cited by 54 publications

References 27 publications

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

Cardiac L‐type Ca²⁺ channel triggers transmitter release in PC 12 cells

Regulation of Ca2+ influx by a protein kinase C activator in chromaffin cells: differential role of P/Q- and L-type Ca2+ channels

Contact Info

Product

Resources

About

Evidence for a dihydropyridine‐sensitive and conotoxin‐insensitive release of noradrenaline and uptake of calcium in adrenal chromaffin cells

Abstract: These results show that in these neurone-like cells, release may be effected by calcium influx through DHP-sensitive but co-conotoxin-insensitive VSCC, a result inconsistent with the suggestion that w-conotoxin blocks both L-type and N-type neuronal calcium channels.

Cited by 54 publications

References 27 publications

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

L-type calcium channels in adrenal chromaffin cells: Role in pace-making and secretion

Cardiac L‐type Ca2+ channel triggers transmitter release in PC 12 cells

Regulation of Ca2+ influx by a protein kinase C activator in chromaffin cells: differential role of P/Q- and L-type Ca2+ channels

Contact Info

Product

Resources

About

Cardiac L‐type Ca²⁺ channel triggers transmitter release in PC 12 cells