Optimization of capsaicin-induced dermal blood flow measurement by laser Doppler imaging in cynomolgus macaque.

BACKGROUND: Capsaicin is used in several areas of non-human primate research including allodynia and dermal blood flow (DBF). The capsaicin-induced DBF increase was measured using laser Doppler imaging (LDI), but this response is known to diminish upon repeated topical applications. Refinement of the experimental procedures could improve the rigor and reproducibility of the DBF migraine model. METHODS: Optimal anatomical site in cynomolgus was determined, and conditions and experimental settings for DBF measurement using LDI were established. Then, two study design trial structures were compared. RESULTS: Medial thigh was the preferrable site, and an ethanol-Tween 20 formulation of capsaicin was desirable. A 1-week washout for contralateral side or 2-week washout for ipsilateral side was necessary to eradicate capsaicin desensitization. CONCLUSIONS: With the established technicality in DBF measurements in cynomolgus macaques, the capsaicin-induced DBF model may be utilized in translational medical research in developing migraine therapeutics.

Evidence of simian retrovirus type D by polymerase chain reaction.

BACKGROUND: Over the past few years, there have been reports of finding Simian retrovirus type D (SRV) in macaque colonies where some animals were characterized as antibody positive but virus negative raising questions about how SRV was transmitted or whether there is a variant strain detected by antibody but not polymerase chain reaction (PCR) in current use. METHODS: We developed a three-round nested PCR assay using degenerate primers targeting the pol gene to detect for SRV serotypes 1-5 and applied this newly validated PCR assay to test macaque DNA samples collected in China from 2010 to 2015. RESULTS: Using the nested PCR assay validated in this study, we found 0.15% of the samples archived on FTA® cards were positive. CONCLUSIONS: The source of SRV infection identified within domestic colonies might have originated from imported macaques. The multiplex nested PCR assay developed here may supplement the current assays for SRV.