Improvement of the optical imaging technique for intact rat brain using a plano-concave lens

Table 1 Parameters associated with optical recordings obtained from 9 elements at the marginal zone of the image with a plano-concave lens or 4 % agarose

Numerals in columns 2–7 are the average and the standard deviation (n = 4) of photocurrent generated by fluorescent light with the plano-concave lens or 4 % agarose. Each parameter was measured trial-by-trial from a single sweep optical signal of neural activity induced by electrical stimulation to the forelimb, as shown in Fig. 2, and then averaged 8 trials in the same individual. Column 1 gives element position (row and column number) in the matrix array photodiode. As shown in Fig. 2, 3 × 3 contiguous elements, at the marginal zone of the image, were selected. Columns 2 and 5 give the change of fluorescence due to neural response activities in pA. Columns 3 and 6 give the peak-to-peak noise level in pA. Columns 4 and 7 give the background fluorescence intensity in nA. Lens/agarose represents the ratio of the data with lens to those with agarose, respectively. Paired t test for the values in each element of each animal (i.e. the comparison of 36 values from each 9 elements in respective 4 animals) showed that the signal size was significantly different between the plano-concave lens and agarose (P < 0.001) but the noise level was not (P = 0.472). The background light intensity was set to have almost the same value at the center element (17–15) for all the recordings by regulating the excitation intensity (see details in the text)

ISSN: 1880-6562