Autotomy following nerve injury: Genetic factors in the development of chronic pain

Abstract

Several weeks following transection and ligation of the hind limb nerves in rats, the animals often attack their anaesthetic foot ("autotomy"). This behaviour is thought to reflect a sensory pathology analogous to anaesthesia dolorosa. We report here that the extent of autotomy varies greatly in genetically different populations of rats. Rats of one population, LC2, showed high autotomy levels; rats of another, LC1, showed very low autotomy levels. The main genetic difference between these two populations is the presence of inbred Lewis rat stock in the LC1 population. Pure Lewis strain rats proved to have very low autotomy levels. Thus, constitutional differences between different rat populations effect the extent of autotomy. These data may bear on the fact that after seemingly identical nerve injuries, some humans develop chronic pain syndromes and others do not. Our rat strains may provide a model for investigating the physiological basis of constitutional susceptibility to chronic pain.

Functional assessment of sciatic nerve reconstruction: Biodegradable poly (DLLA-?-CL) nerve guides versus autologous nerve grafts

“…Similar findings were reported by Zellem et al 47 They reproduced the results of de Medinaceli's protocol and refined his technique and showed self-mutilation of the limb supplied by the sciatic nerve in 39 of the 69 rats (57%) after sciatic nerve repair. Inbal et al 48 reported that the extent of automutilation (e.g. autotomy, self-mutilation) varies greatly in genetically different populations of rats.…”

Electrophysiologic assessment of sciatic nerve regeneration in the rat: Surrounding limb muscles feature strongly in recordings from the gastrocnemius muscle

“…Lewis rats had originally been chosen for the previous study on account of their proven resistance to autotomy after sci- (Carr et al, 1992;Inbal et al, 1980;Panerai et al, 1987), and on account of their sciatic nerves being particularly suitable from an anatomical point of view (Rupp et al, 2007a).…”

Differences in forebrain activation in two strains of rat at rest and after spinal cord injury

“…Early studies showed that the development of autonomy, a presumed sign of neuropathic pain, differs markedly in different strains of rat after total nerve transection (Inbal et al, 1980;Wiesenfeld and Hallin, 1981). Such strain-dependent variability in autonomy has subsequently been confirmed in both rats and mice (Panerai et al, 1987;Devor and Raber, 1990;Cohn and Seltzer, 1991;Carr et al, 1992;Defrin et al, 1996;Mogil et al, 1999).…”