Manual Patch Clamp Screen
Profiles ion channels and compares concentration-response parameters
Conventional manual patch clamp assays provide the most versatile and accurate assessment of drug interactions with ion channels. For instance, continuous superfusion of cells in manual patch clamp improves the accuracy of testing difficult (e.g., “sticky”) compounds versus automated patch clamp and can be performed at physiologic temperature. The IC50 concentration-response assays provide important benchmarks for structure-activity evaluation, whereas the Screens tests compounds within structural or therapeutic groups against one or more ion channels.
Assay Features:
- Gold-standard, functional cell-based ion channel assay
- Quantitative profiling
- Provides mechanisms
- Physiologic temperature available for most assays
- Range-finding pre-test available for concentration-response assays
- HPLC concentration-verification available
| Assay Parameters: | IC50 | Screen |
|---|---|---|
| Platform | Manual patch clamp | Manual patch clamp |
| Number of concentrations | 4 | 1 – 2 |
| Number of replicates per concentration | 3 | 2 – 3 |
| Positive control (# of measurements) 2 | 2 | 2 |
| Vehicle control (1 concentration N=3) | optional | optional |
| Assay temp: room (RT) or physiological (PT) | RT or PT | RT or PT |
| Concentration range-finding pre-test | + | n/a |
| Protocol & report | GLP format without QAU review | Results Table |
| Cumulative curves | + | n/a |
| Collection of analytical samples | optional | optional |
| Electronic (pdf) report provided | + | + |
LEGEND: hERG concentration-response assay. A: Superimposed patch clamp recordings (upper section) obtained before (control) and during application of 10 and 100 nM cisapride. At the end of the recording period 500 nM E-4031, a selective hERG channel blocker, was applied. The lower section of the figure shows the stimulus voltage pattern. B: Peak current amplitude versus time during repetitive stimulation at 0.1 pulses/second. C: Concentration-response relationship. Mean ± SEM, n = 4 cells/concentration. IC50 = 0.0234 μM.
| Family | Channel |
|---|---|
| Ligand-gated | 5-HT3A |
| Calcium, voltage-gated | Cav1.2/β2/α2δ (Cardiac L-type) |
| Cav2.2/β3/α2δ (N-type) | |
| Cav3.2 (T-type) | |
| Sodium, epithelial | ENaC |
| Hyperpolarization-gated | HCN4 |
| Ligand-gated | GABA-A (α1/β2/γ2) |
| GABA-A (α2/β2/γ2) | |
| GABA-A (α5/β2/γ2) | |
| Potassium, inward rectifier | Kir2.1 (IK1) |
| Kir3.1/Kir3.4 | |
| Potassium, voltage-gated | Kv1.5 |
| Kv1.6 | |
| Kv11.1 (hERG) | |
| Kv4.2/KChIP2.2 | |
| Kv4.3 | |
| Kv7.1 (KvLQT1-minK; KCNQ1-KCNE1) | |
| Kv7.2/Kv7.3 (KCNQ2/KCNQ3) | |
| Kv7.3/Kv7.5 (KCNQ3/KCNQ5) | |
| Kv7.4 (KCNQ4) | |
| Sodium, voltage-gated | Nav1.1 |
| Nav1.2 | |
| Nav1.3 | |
| Nav1.5 | |
| Nav1.6 | |
| Sodium/calcium exchanger | NCX1 |
| Ligand-gated | Nicotinic receptor (nAChR) α1 |
| Nicotinic receptor (nAChR) α3 | |
| NMDA receptor (NR1/NR2A) | |
| NMDA receptor (NR1/NR2B) | |
| Potassium, calcium-activated | SK2 (KCa2.2) |
| TRP (transient receptor potential) | TRPA1 |
| TRPC1 | |
| TRPC4 | |
| TRPC6 | |
| TRPM2 | |
| TRPM4 | |
| TRPV1 | |
| TRPV4 | |
| TRPV6 |
Optional assays:
- Dose Solution Analysis – GLP & non-GLP; verify applied concentrations with analytical sample testing of doses
- Use-dependence analysis
- Temperature-dependence analysis
Additional study options:
- Additional copies of final report
- Copies of solution worksheets & data-collection forms
For a quote or additional information, please email inquiries@chantest.com or call 216-332-1665.
Additional Services