Showing papers on "Uca pugilator published in 1992"

Hormonal Control of the Molt Cycle in the Fiddler Crab Uca pugilator

Abstract: Comparison of the circulating steroids in the blood of crabs lacking neurosecretory eyestalk centers and crabs with those centers intact (but lacking several walking legs) has revealed differences in vivo that can be attributed to eyestalk factors. It is concluded that eyestalk factors (including the putative molt-inhibiting hormone, MIH): 1) exert control in vivo over production of 25-deoxyecdysone by the crab Y-organ, 2) control cyclic steroid production throughout anecdysis and parts of proecdysis and 3) are not solely responsible for the increased steroid production that occurs during late proecdysis. Using the data presented here and previously published data, a simple feedback model for the control of Y-organ activity is proposed. The model suggests that the Y-organs of the crab Uca pugilator are modestly active during anecdysis but become further activated during late proecdysis. The increased activation requires more than eyestalk removal and may involve additional extra-eyestalk factors.