Reddy P S, Fingerman M
Department of Ecology, Evolution, and Organismal Biology, Tulane University, Louisiana 70118, USA.
Ecotoxicol Environ Saf. 1995 Jun;31(1):69-75. doi: 10.1006/eesa.1995.1045.
The effects of cadmium exposure on the color change system of the fiddler crab, Uca pugilator, were determined. Crabs were either immersed in 10 ppm cadmium chloride solutions or injected with 8.5 micrograms cadmium/g body weight. The crabs exposed to cadmium, either by injection or immersion, were less able to bring about dispersion of the pigment in their integumentary melanophores than were the unexposed crabs. Cadmium did not affect the melanophores directly. This decreased black pigment dispersion was apparently due to effects of cadmium on the neuroendocrine processes that control the melanophores. The neuroendocrine complex in the eyestalk is the source of a black pigment-dispersing hormone (BPDH). Eyestalks of crabs kept in clean water contained 3.27 times more BPDH than did the eyestalks of the cadmium-exposed crabs. Histological studies revealed that cadmium exposure results in depletion of the neurosecretory material in the eyestalks and brain. It is hypothesized that cadmium inhibits BPDH synthesis in neurosecretory (neuroendocrine) cells, resulting in decreased ability of exposed crabs to disperse their black pigment.
研究了镉暴露对招潮蟹（学名：Uca pugilator）颜色变化系统的影响。将螃蟹要么浸入10 ppm的氯化镉溶液中，要么以每克体重注射8.5微克镉的方式进行处理。通过注射或浸入方式接触镉的螃蟹，比起未接触镉的螃蟹，其体表黑素细胞中色素的分散能力更弱。镉不会直接影响黑素细胞。这种黑色色素分散能力的下降显然是由于镉对控制黑素细胞的神经内分泌过程产生了影响。眼柄中的神经内分泌复合体是黑色色素分散激素（BPDH）的来源。养在清洁水中的螃蟹的眼柄所含的BPDH比接触镉的螃蟹的眼柄多3.27倍。组织学研究表明，镉暴露会导致眼柄和大脑中的神经分泌物质减少。据推测，镉会抑制神经分泌（神经内分泌）细胞中BPDH的合成，从而导致接触镉的螃蟹分散其黑色色素的能力下降。
