Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, OH 43210, USA.
J Vet Intern Med. 2010 Nov-Dec;24(6):1343-9. doi: 10.1111/j.1939-1676.2010.0613.x. Epub 2010 Oct 14.
Dogs have a high prevalence of disc-associated cervical spinal cord disorders. Despite this, there are no descriptions of the micromorphometry or cellular characteristics of canine cervical intervertebral discs.
HYPOTHESIS/OBJECTIVES: To compare micromorphometric and cellular characteristics at 4 disc regions (outer annulus [OA], inner annulus [IA], transitional zone [TZ], nucleus pulposus [NP]). We hypothesized that measurements would differ between chondrodystrophic (CH) and nonchondrodystrophic (NCH) dogs.
Six CH dogs and 6 NCH dogs, under 3 years old.
Histologic sections of all cervical discs from each dog were examined. Micromorphometric variables included relative ratio of ventral to dorsal annulus fibrosus (AF), number and mean width of AF fibers, and relative percentage of NP. Cellular variables included cell density, morphology, and grouping.
The NP from CH dogs was smaller, more rounded, and more dorsally located compared with that from NCH dogs. The NP occupied a greater proportion of the disc in NCH dogs compared with CH dogs (27.7 versus 15.8%; P<.001). The ratio of ventral to dorsal AF was approximately 3:1 in the CH group and 2:1 in the NCH group. Cellular variables were region dependent. Cell density was 2.4-fold higher in the OA compared with the NP. Approximately 50 of NP cells and 4.5% of OA cells occurred in groups.
Micromorphometric variables differed by CH status. Cellular variables differed by disc region. Our findings potentially can explain the high incidence of intervertebral disc extrusions in CH dogs compared with NCH dogs.
狗的颈椎椎间盘与脊椎骨相关的疾病发病率很高。尽管如此，目前还没有关于犬颈椎椎间盘的微观形态和细胞特征的描述。
假说/目的：比较 4 个椎间盘区域（外纤维环[OA]、内纤维环[IA]、过渡区[TZ]、髓核[NP]）的微观形态和细胞特征。我们假设这些测量值在软骨发育不全（CH）和非软骨发育不全（NCH）的狗之间会有所不同。
6 只 CH 犬和 6 只 NCH 犬，年龄均在 3 岁以下。
对每只狗的所有颈椎椎间盘进行组织学切片检查。微观形态学变量包括腹侧纤维环与背侧纤维环的相对比例、纤维环纤维的数量和平均宽度以及 NP 的相对百分比。细胞变量包括细胞密度、形态和分组。
与 NCH 犬相比，CH 犬的 NP 更小、更圆、更位于背侧。与 CH 犬相比，NCH 犬的 NP 占据了椎间盘的更大比例（27.7%对 15.8%；P<.001）。CH 组的腹侧纤维环与背侧纤维环的比例约为 3:1，而 NCH 组为 2:1。细胞变量与区域有关。OA 中的细胞密度是 NP 的 2.4 倍。大约 50%的 NP 细胞和 4.5%的 OA 细胞成团存在。
CH 状态的微观形态学变量不同。细胞变量因椎间盘区域而异。我们的发现可能可以解释 CH 犬比 NCH 犬更易发生椎间盘突出的高发病率。
