. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. B "Serum ^Carcass Midgut Gland + Hindgut 9 24 14 HOURS AFTER INJECTION. 'Serum Carcass Midgut Gland + Hindgut 9 24 FIGURE 4. Pattern of change of radiolabeled metabolites in (A) normal crabs in stage D,, and (B) LBA crabs. Changes in the total radioactivity in serum, carcass and midgut gland - hindgut over a 24-hr period are indicated by the diagonal lines between the bars for each time point. The amount of the various metabolites in each tissue at each time point is indicated : ecdysone (bars with vertical lines); 20-h
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. B "Serum ^Carcass Midgut Gland + Hindgut 9 24 14 HOURS AFTER INJECTION. 'Serum Carcass Midgut Gland + Hindgut 9 24 FIGURE 4. Pattern of change of radiolabeled metabolites in (A) normal crabs in stage D,, and (B) LBA crabs. Changes in the total radioactivity in serum, carcass and midgut gland - hindgut over a 24-hr period are indicated by the diagonal lines between the bars for each time point. The amount of the various metabolites in each tissue at each time point is indicated : ecdysone (bars with vertical lines); 20-hydroxyecdysone (bars with diagonal lines); 20,26- dihydroxyecdysone (filled bars); total polar conjugates (empty bars). 20-Hydroxyecdysone is the primary metabolite of ecdysone; however, beginning at 4 hr, further hydroxylation to 20,36-dihydroxyecdysone becomes significant. The rate of loss of 20-hydroxyecdysone is slightly accelerated following LBA from k = to (Figs. 2B, 3B). Carcass. The rate of loss of total radioactivity from the carcass is relatively unaffected by the re-autotomy of partial regenerates; the rate coefficients are k = and for normal crabs in stage D0 and following LBA, respec- tively (Fig. 1). 20-Hydroxyecdysone and 20,26-dihyroxyecdysone are the primary metabolites observed in the carcass; the relative proportions of these metabolites increase steadily over the experimental period. The rate of loss of 20-hydroxyecdysone from the carcass more than doubles from k = for normal crabs in stage Dn to k = within a few hours after re-autotomy (Figs. 2E, 3E). Midgut gland. The major metabolites present in the mid-gut gland are polar conjugates of the ecdysteroids. The conjugate of ecdysone is the most abundant metabolite shortly after injection; however, as the concentration of this metabolite decreases, the amount of the conjugate of 20-hydroxyecdysone increases rapidly. In crabs in stage D0, the amount of polar
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
