Fig 1.
(A) The diagrammatic representation of shrimps’ survival according to starvation and re-feeding. (B-E) The midgut of non-starved specimens of N. davidi. (B) A longitudinal section through the hepatopancreas with numerous caeca (ca). Light microscopy. Bar = 15 μm. Midgut lumen (l), basal lamina (arrowheads). (C) A transverse section through the anterior fragment of the intestine with regenerative cells (arrows) distributed among the basal regions of the digestive cells (dc). Light microscopy. Bar = 23 μm. (D-E) Mitochondrial potential in the N. davidi midgut epithelium. Active mitochondria with a high membrane potential (red signals), inactive mitochondria with a low membrane potential (green signals). JC-1 cationic dye. Confocal microscope. (D) Hepatopancreas in non-starved animals. Bar = 10 μm. (E) Intestine in non-starved animals. Bar = 8 μm.
Fig 2.
Mitochondrial potential in the N. davidi midgut epithelium.
Active mitochondria with a high membrane potential (red signals), inactive mitochondria with a low membrane potential (green signals), nuclei (blue signals). JC-1 cationic dye, Hoechst 33342 staining. Confocal microscope. (A) Hepatopancreas in animals starved for 7 days. Bar = 10 μm. (B) Intestine in animals starved for 7 days. Bar = 5 μm. (C) Hepatopancreas in animals starved for 14 days. Bar = 5 μm. (D) Intestine in animals starved for 14 days. Bar = 10 μm. (E) Hepatopancreas in animals starved for 21 days. Bar = 5 μm. (F) Intestine in animals starved for 21 days. Bar = 5 μm.
Fig 3.
Mitochondrial potential in the N. davidi midgut epithelium.
Active mitochondria with a high membrane potential (red signals), inactive mitochondria with a low membrane potential (green signals), nuclei (blue signals). JC-1 cationic dye, Hoechst 33342 staining. Confocal microscope. (A) Hepatopancreas in animals re-fed for 4 days after 14 days of starvation. Bar = 5 μm. (B) Intestine in animals re-fed for 4 days after 14 days of starvation. Bar = 5 μm. (C) Hepatopancreas in animals re-fed for 7 days after 14 days of starvation. Bar = 5 μm. (D) Intestine in animals re-fed for 7 days after 14 days of starvation. Bar = 5 μm. (E) Hepatopancreas in animals re-fed for 14 days after 14 days of starvation. Bar = 5 μm. (F) Intestine in animals re-fed for 14 days after 14 days of starvation. Bar = 10 μm.
Fig 4.
A diagrammatic representation of the average percentage of cells with depolarized mitochondria in the hepatopancreas (A) and intestine (B) in N. davidi exposed to starvation and after refeeding.
a, b, c– starvation, A–re-feeding—determination whether the outcome of each step varies in a statistically significant way from the previous step. The same letter symbols represent no significant differences. Different graph symbols (♠♣♦♥*#) mean that the results differ significantly from the result under control.
Table 1.
Percentage [%] of intestinal and hepatopancreatic epithelial cells with active mitochondria in the N. davidi that were re-fed after 14 days of starvation.
Fig 5.
Ultrastructure of the midgut epithelium in N. davidi.
TEM. Mitochondria (m), midgut lumen (l), microvilli (mv), nucleus (n), cisterns of RER (RER), vacuoles (v), autophagosomes (au). (A) Hepatopancreas in non-starved animals. Bar = 1.5 μm. (B) Intestine in non-starved animals. Bar = 1 μm. (C) Hepatopancreas in animals starved for 7 days. Bar = 1 μm. (D) Intestine in animals starved for 7 days. Bar = 1 μm. (E) Hepatopancreas in animals starved for 14 days. Bar = 0.15 μm. (F) Intestine in animals starved for 14 days. Bar = 1 μm. (G) Hepatopancreas in animals starved for 14 days. Bar = 1.5 μm.
Fig 6.
Ultrastructure of the midgut epithelium in N. davidi.
TEM. Mitochondria (m), midgut lumen (l), microvilli (mv), nucleus (n), cisterns of RER (RER), vacuoles (v), autophagosomes (au). (A) Hepatopancreas in animals starved for 21 days. Bar = 2.6 μm. (B) Intestine in animals starved for 21 days. Bar = 1 μm. (C) Hepatopancreas in animals re-fed for 4 days after 14 days of starvation. Bar = 1.5 μm. (D) Intestine in animals re-fed for 4 days after 14 days of starvation. Bar = 0.5 μm. (E) Intestine in animals re-fed for 4 days after 14 days of starvation. Bar = 0.5 μm.
Fig 7.
Ultrastructure of the midgut epithelium in N. davidi.
TEM. Mitochondria (m), midgut lumen (l), microvilli (mv). (A) Hepatopancreas in animals re-fed for 7 days after 14 days of starvation. Bar = 1 μm. (B) Intestine in animals re-fed for 7 days after 14 days of starvation. Bar = 1 μm. (C) Hepatopancreas in animals re-fed for 14 days after 14 days of starvation. Bar = 0.5 μm. (D) Intestine in animals re-fed for 14 days after 14 days of starvation. Bar = 1 μm.
Table 2.
Number of adult specimens of N. davidi that were used in each part of the experiment.