Leucocyte Response In Nigerian Indigenous Dogs With Surgically Induced Radial Nerve Paralysis
Surgical stress is known to cause varied leucocyte responses (Kim and Sakamoto, 2006). The anaesthetic agent used may also modify intra or post surgical leucocyte response e.g. propofol producing a dose-dependent inhibition of phagocytosis in vitro (Heine et al., 2000). Surgery constitute a form of traumatic stress, which varies with the duration and invasiveness of the procedure undertaken (Plunkett, 2001). This stressful condition alters the body\'s homeostasis which is further aggravated by the release of adrenocorticotrophic hormone (ACTH) in the body (Guyton and Hall, 1996). Radial nerve damage and subsequent repair is a major surgical procedure that is not commonly reported in dogs and its effect on leucocyte response has not been documented. The radial nerve resection was primarily undertaken to evaluate various management protocols, with the aim to adapting them for clinical management of radial nerve damage in dogs. In this report, we present the total and differential leucocyte response in Nigerian Indigenous dogs with radial nerve resection. Major surgeries, such as cardiopulmonary and coronary artery bypass are known to trigger an inflammatory response, leading to the activation of leucocytes, platelets and endothelial cells (Asimakopoulos and Taylor, 1998; Asimakopoulos et al., 2000; Ngaage, 2003).Major surgeries reportedly also produce PMNL (neutrophil) dysfunction (Wakefield et al., 1993). In surgical stress, massive neutrophil and monocyte trafficking into tissues (surgical sites) have been documented (Viswanathan and Dhabhar, 2005; Zaldivar et al., 2006) and is thought to occur as a result of direct response of the neutrophils to the effect of tumour necrosis factor-α (TNF-α) produced during inflammation/ healing (Viswanathan and Dhabhar, 2005). Platelet activating factor (PAF) and CD18 have also been reported to mediate neutrophil infiltration into tissues (surgical sites) (Beyer et al., 1998), while monocyte trafficking into tissues is believed to be mediated by the combined effects of TNF-α and lymphotactin (LTN).
Keywords: Leucocyte response, Mongrel dogs, Radial nerve, Paralysis
Nigerian Veterinary Journal Vol. 27 (3) 2006 pp. 91-95