Journal: Molecular Pain

Article Title: Nociceptive signaling through transient receptor potential vanilloid 1 is regulated by Cyclin Dependent Kinase 5-mediated phosphorylation of T407 in vivo

doi: 10.1177/17448069221111473

Figure Lengend Snippet: Behavioral Testing. a. Oral aversion to capsaicin was measured in the WT and TRPV1 T407A mice using the lickometer. The duration of drinking behavior from the mice was recorded for 1 h. At 0.15 μM, TRPV1 T407A show less aversion to capsaicin (3 trials using N = 6 mice), although at higher concentrations (1.5 and 15 μM) no significant difference in drinking behavior was seen. b. Mouse grimace scale was used to score facial expressions of pain and discomfort after injection of 0.1% Capsaicin injection into the whisker pad of the mouse. While not significant, TRPV1 T407A show a trend towards reduced facial signs of pain as compared to WT littermate controls ( N = 3). c. The hot plate assay was used to monitor basal nocifensive behaviors in the TRPV1 T407A mice. The hot plate was set at 50°C and hindpaw withdrawal was timed ( N = 4). TRPV1 T407A mice display increased hindpaw withdrawal latency compared to WT mice, suggesting reduced peripheral aversion to noxious heat (3 trials).

Article Snippet: Oral aversion to the TRPV1 agonist capsaicin (MilliporeSigma, Burlington, MA) was measured using the EthoVision instrumented observation cage with the lickometer add-on (Noldus, Leesburg, VA).

Techniques: Injection, Whisker Assay

Journal: Scientific Reports

Article Title: Phosphorylation of the Transient Receptor Potential Ankyrin 1 by Cyclin-dependent Kinase 5 affects Chemo-nociception

doi: 10.1038/s41598-018-19532-6

Figure Lengend Snippet: Response to allyl isothiocyanate (AITC) in animals with genetically driven alterations in Cdk5 kinase activity. ( A – E ) Genetically engineered mice with either increased or reduced Cdk5 activity were tested for oral aversion to AITC using a lickometer. Water-deprived C57BL/6 and FVB/N mice were tested for 1 h using the lickometer with a free access to water containing different concentrations of AITC. The behavior is expressed as a % of the baseline licking responses for plain water as compared to AITC. The p35KO mice and Cdk5CoKo mice (C57BL/6:129/SvJ background) were less sensitive to water dosed with AITC (increased licking behavior) as compared to the controls (one way ANOVA, *P < 0.05 at 10 μM, *P < 0.051 at 100 μM and ***P < 0.001 at 100 & 1000 μM). Conversely, the Tgp35 mice show higher aversion and hypersensitivity to 100 and 1000 μM AITC (unpaired t -test, ***P < 0.001) as evident by the decreased number of licks. SEM from four animals during five different measurements.

Article Snippet: Water-deprived (15 h) animals were placed in the lickometer cages (Habitest system, Coulbourn Instruments, Whitehall, PA) where a computer-operated system monitored their licking behavior for a period of 1 hour.

Techniques: Activity Assay