Newt limb regeneration

Kinmer, C. R. and Brockes, J. (1984) Monoclonal antibodies identify blastemal cells derived from differentiating muscle in newt limb regeneration. Nature (London) 308,67-69. 

Mescher, A. L. (1976) Effects on adult newt limb regeneration of partial and complete skin flaps over the amputation surface. J. Exp. Zool. 195,117-128. 

Radiation adversely affects limb regeneration of amphibians, alters DNA metabolism, and increases the frequency of chromosomal aberrations and liver lesions (Table 32.25). In some species of amphibians and reptiles, as in many mammals, mortality rates after acute exposure to radiation do not stabilize within 30 days — effectively invalidating the conventional LD50 (30-day postexposure) value. In the rough-skinned newt (Taricha granulosa), for example, the minimal LD50 dose at 200 days after irradiation was 2.5 Gy, compared with 350 Gy at 30 days (Willis and... 

Landesman, R.H. and W.S. Douglas. 1990. Abnormal limb regeneration in adult newts exposed to a pulsed electromagnetic field. Teratology 42 137-145. 

L. F. (1977) Bioelectricity and regeneration large currents leave the stumps of regenerating newt limbs. Proc. Natl. Acad. Sci. USA 74, 4528 532. 

A host of different species have been used over the past century for limb regeneration studies, including the European crested newt, Triturus cristatus, which is now a protected species. Today, however, four species predominate. One is the eastern spotted newt of North America, Notophthalmus viridescens, which is used as an adult. The adults of this species are common, adaptable to... 

Landesman, R. H. and Copeland, K. C. (1988) Bioengineered human growth hormone supports limb regeneration in the hypophysectomized newt Notophthalmus viridescens. J. Exp. Zool. 248,247-250. 

Newt, Notophthalmus viridescens adults, single acute exposure of 20 Gy, one limb shielded or 22 Gy, whole body, no limbs shielded Frog, Rana sp., single acute exposure Forelimb regeneration completely suppressed when limbs to be amputated were irradiated directly. Irradiated limbs had severe and protracted inflammation, with total resorption of the affected limbs in 85% of the cases. Shielded limbs subsequently amputated had delays — but not suppression — in rate of forelimb regeneration and skin graft rejection 4... 

Maneb at aqueous concentrations of 5 ppm resulted in delayed development of amputated forearms in male and female newts, with reduced melanogenesis and malformations of regenerating limbs (Arias and Zavanella 1979 Zavanella et al. 1984). However, in light of the relevant pathways of pesticide exposure in humans, the relevance of this model system to human development is not clear. 

Young axolotl larvae will regenerate their limbs in 2-3 wk, whereas adult newts take 2-3 mo, hut the processes they go through are identical. 

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