PrecisION hHCN3-HEK Recombinant Cell Line

PrecisION hHCN3-HEK Recombinant Cell Line

Upstate (Millipore)

2 mL

Recombinant HEK293 cell line expressing the human hyperpolarization-activated, cyclic nucleotide-gated potassium channel 3 (HCN3).

Four different hyperpolarization-activated, cyclic nucleotide-modulated (HCN) channel isoforms have been cloned (HCN1-4). They can be distinguished by differing sensitivity to modulators such as cAMP, different V½ values of activation and different activation kinetics. Even though they are structurally similar to Kv channels they are activated by strong hyperpolarizing voltages rather than depolarizing voltages. As such the channels are active at or around the resting potential and contribute to pacemaker activity both in the heart and CNS. There is considerable overlap in the expression of these isoforms in different tissues (Moosmang et al., 2001, Stieber et al., 2005) and it is highly likely that they can form heteromultimers (Altomare et al., 2003, Chen et al., 2001, Brewster et al., 2005).

Altered HCN channel expression has been implicated in increased neuronal hyperexcitability following seizures and may represent a novel drug target for the treatment of seizure-evoked epilepsy (Brewster et al., 2005). HCN channels also appear to have a role in some models of neuropathic pain where the spontaneous firing of damaged nerves and therefore the sensation of pain can be alleviated by the selective HCN blocker ZD7288 (Chaplan et al., 2003).

HEK293 cells expressing hHCN3 were characterised in terms of their biophysical and pharmacological properties using whole-cell patch clamp techniques and IonWorks™ HT electrophysiology. The biophysical properties are typical of hHCN3 both in terms of V½ of activation (–81.6 ± 0.53 mV, n=7) and the time course of activation (e.g. 1791 ± 80 ms at -100 mV, n=3). The mean current amplitude was 5.4 ± 1.4 nA at -130 mV (n =7) and reversal potential measurements indicated permeability to both Na+ and K+ (PNa/PK around 0.2 to 0.3) typical of HCN channels. According to a published report a negative shift in the V½ of activation in the presence of cAMP (100 µM) is peculiar to hHCN3 since other members of the HCN family exhibit, to varying degrees, a positive shift in V½. This negative shift was confirmed in the present study (around -6 mV), providing further evidence for selective functional expression of hHCN3 channels in this cell line. Currents were also dose-dependently inhibited by the inorganic cation Cesium (Cs+) with an IC50 value of around 100 µM, close to reported values. Channel expression was monitored using IonWorks™ HT over 37 passages. Typically over 50% of cells expressed currents of >200 pA and therefore should be suitable for many screening applications.

Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.

Putative hyperpolarization-activated ion channel exhibiting weak selectivity for potassium over sodium ions

Human

Mycoplasma Testing:
The cell line has been screened to confirm the absence of Mycoplasma species

HEK

Ion Channel Cell Lines

Pack contains 2 vials of mycoplasma-free cells, 1 ml per vial

Upstate

293 cell line

hHCN3

2 x 1 ml aliquots

Hyperpolarized

Ion Channels

PrecisION hHCN3-HEK Recombinant Cell Line