Figure 4
From: Optogenetic stimulation of cholinergic fibers for the modulation of insulin and glycemia
Measurement of pancreatic blood perfusion using contrast enhanced ultrasound imaging of microbubbles. (A) B-mode and sub-harmonic contrast mode images in the abdominal cavity. Microbubble-generated sub-harmonic contrast is observed in the tissues during microbubble infusion and during reperfusion following flash-destruction. Red arrow = optical cannula/needle tip, P = pancreas (tail), S = spleen, K = kidney. (B) Example single recording reperfusion data and curve fit before and after laser stimulation for a ChAT-ChR2 mouse and wild-type mouse. Intensity is based on microbubble (MB)-generated sub-harmonic contrast as MBs perfuse back into the pancreas following flash destruction. Curves are fitted to a single component inverse exponential to extract the rate of signal elevation (kr = 1/time constant of recovery). Upper panels (blue points and curves) are from a ChAT-ChR2 mouse and lower panels (black points and curves) are from a wild-type mouse. (C) Mean reperfusion rate in ChAT-ChR2 mice and wild-type mice, prior to laser stimulation and after 25 min of laser stimulation. Data in C presented as the mean over n = 8 ChaT-ChR2 recordings and n = 5 WT recordings. Error bars represent standard error in the mean.
