A CNS Catecholaminergic Cell Line Expresses Voltage-gated Currents

Abstract

CATH.a is a central nervous system (CNS) catecholaminergic cell line derived from a transgenic mouse carrying the SV40 T antigen oncogene under the transcriptional control of regulatory elements from the rat tyrosine hydroxylase gene (Suri et al., 1993). CATH.a cells express several differentiated neuronal characteristics including medium and light chain neurofilament proteins, synaptophysin, tyrosine hydroxylase, and dopamine beta-hydroxylase; they synthesize dopamine and norepinephrine. Conversely, they do not express glial-specific fibrillary acidic protein. To establish definitively that CATH.a cells are of neuronal origin, we characterized the repertoire of voltage-gated inward currents expressed by CATH.a cells. Such inward currents are necessary for neuronal excitability. We report that all CATH.a cells possess a tetrodotoxin-sensitive sodium current (peak amplitude = 590 +/- 319 pA) and 68% possess a high voltage-activated calcium current (peak amplitude = 175 +/- 67 pA). Pharmacological analyses suggest that individual cells express varying levels of L- and N-type calcium current, but no P-type current. In addition, in 55% of the cells with a calcium current, about a half of this current is resistant to selective antagonists for L- and N-type currents, suggesting that another calcium current exists in these CATH.a cells which is not L-, N-, or P-type. The heterogeneous pattern of current detected persisted in several CATH. a subclones, suggesting that factors other than genetic variability influence current expression. The demonstration that CATH.a cells express these currents indicates that they have excitable membrane properties characteristic of neurons. Although many peripheral nervous system (PNS) cell lines exist, very few CNS cell lines with differentiated neuronal properties exist. Since the CATH.a cells can be grown continuously in large amounts, they may be useful for purifying, characterizing, and/or cloning various neuronal-specific molecules and thereby may add to our understanding of CNS catecholaminergic neurons.

Downregulated Kv4.3 expression in the RVLM as a potential mechanism for sympathoexcitation in rats with chronic heart failure

“…We, therefore, hypothesized that a similar mechanism underlies the downregulation of Kv4.3 expression in neurons. CATH.a cells are a central nervous system catecholaminergic cell line derived from the mouse locus coeruleus and express a variety of pan-neuronal markers, including voltage-gated K ϩ channels (20,38). In the present study, we demonstrate the colocalization of the AT 1 R and Kv4.3 protein in the membrane of CATH.a cells (Fig.…”

“…CATH.a cells were originally derived from a brain stem catecholaminergic neuronal mouse cell line (38) and displays a differentiated neuronal phenotype and excitable membrane characteristics (20).…”

Differentiation of an adult neuron cell line increases susceptibility to rabies infection.

“…Both cell lines express biochemical neuron markers (synaptophisin 38 and neurofilament) and show neuronal physiological characteristics (voltage-dependent sodium and calcium currents) (18,19). Additionally, CAD cells express other biochemical markers such as β-tubulin III, GAP-43 and sinaptotagmin 65 with stronger intensity (16,20).…”

“…Bearing in mind that there is no CNS adult neuronal line currently available for studies into RV neurotropism (as a possible improved substrate for isolating the virus and its possible use in producing vaccines), the aim of this work was to determine the CAD-R1 susceptibility to rabies infection, in its two states of differentiation, by two variants of a fixed RV strain (CVS-BHK and CVS-MB). (18) and cultured in DMEM/F-12 with 8% foetal bovine serum (FBS, Hyclone) (maintenance medium, MM), 100 U/ml penicillin and 0.1 mg/ml streptomycin also being added. They were kept in 25 cm 2 culture flasks until reaching 80% confluence and then were subcultured and seeded in 24-well plastic dishes, on glass coverslips (treated with 10 µg/ml poly-Llysine) at 1,000 and 2,000 cells per well density for CAD-R1 undifferentiated and differentiated cells, respectively.…”

RNA Interference-Mediated Knockdown of Dynamin 2 Reduces Endocannabinoid Uptake into Neuronal dCAD Cells

“…Interestingly, neurons are not thought to express caveolin-1 but do exhibit lipid raft-related endocytic processes (Cameron et al, 1997). Thus, our studies seek to validate a neuronal-like cell line as a useful model in the study of AEA uptake and to show that AEA uptake can be disrupted by using molecular inhibitors that are specifically targeted to endocytic processes.Cath.a cells display neuronal properties and express panneuronal markers but lack classic neuronal morphology (Suri et al, 1993;Lazaroff, 1996). Cath.a differentiated (CAD) cells are derived from the Cath.a cell line and are characterized by the loss of the immortalizing oncogene present in Cath.a cells (Qi et al, 1997).…”