Figure 1. Morphology, cell size and [Ca²⁺]_i.

A, composite image of scanning electron micrographs of microglial cells at various stages of activation with 1 μg ml⁻¹ LPS from non-activated (left cell, arborized) to fully activated (right cell, ‘fried egg’-shaped). B and C, percentage of ramified (^, ± s.e.m.) and ‘fried egg’-shaped (•, ± s.e.m.) cells per coverslip depending on time in subculture (B, day 1 n = 12, 2 n = 10, 3 n = 9, 4 n = 5, 5 n = 5, 6 n = 8, 7 n = 5 coverslips, 2142 cells) and incubation time in 1 μg ml⁻¹ LPS (C, 0 h n = 32, 3 h n = 6, 6 h n = 8, 12 h n = 4, 24 h n = 9, 48 h n = 8 coverslips, 2211 cells). D and E, cell capacitance (in pF, ± s.e.m.) of microglial cells depending on time in subculture (D, day 1 n = 76, 2 n = 63, 3 n = 110, 4 n = 117, 5 n = 35, 6 n = 38, 7 n = 35 cells) and incubation time in 1 μg ml⁻¹ LPS (E, 0 h n = 335, 3 h n = 40, 6 h n = 49, 12 h n = 29, 24 h n = 155, 48 h n = 43 cells). The controls (0 h LPS) in C and E represent the average data from day 3 to day 7 in B and D, respectively. F and G, intracellular Ca²⁺ changes (F₃₄₀/F₃₈₀) during the first 3 h (F, n = 22, 2 coverslips) and basic internal Ca²⁺ up to 48 h (G) after incubation with 1 μg ml⁻¹ LPS. (G, 0 h n = 47, 3 h n = 57, 6 h n = 78, 12 h n = 54, 24 h n = 26, 48 h n = 45).